diff --git a/conda/recipes/libraft/conda_build_config.yaml b/conda/recipes/libraft/conda_build_config.yaml
index d156f2609b..25493a34fa 100644
--- a/conda/recipes/libraft/conda_build_config.yaml
+++ b/conda/recipes/libraft/conda_build_config.yaml
@@ -71,3 +71,9 @@ cuda11_cuda_profiler_api_host_version:
 
 cuda11_cuda_profiler_api_run_version:
   - ">=11.4.240,<12"
+
+spdlog_version:
+  - ">=1.11.0,<1.12"
+
+fmt_version:
+  - ">=9.1.0,<10"
diff --git a/conda/recipes/libraft/meta.yaml b/conda/recipes/libraft/meta.yaml
index 5203f7b3bd..116f8d9e6e 100644
--- a/conda/recipes/libraft/meta.yaml
+++ b/conda/recipes/libraft/meta.yaml
@@ -63,12 +63,16 @@ outputs:
         {% endif %}
         - cuda-version ={{ cuda_version }}
         - librmm ={{ minor_version }}
+        - spdlog {{ spdlog_version }}
+        - fmt {{ fmt_version }}
       run:
         - {{ pin_compatible('cuda-version', max_pin='x', min_pin='x') }}
         {% if cuda_major == "11" %}
         - cudatoolkit
         {% endif %}
         - librmm ={{ minor_version }}
+        - spdlog {{ spdlog_version }}
+        - fmt {{ fmt_version }}
     about:
       home: https://rapids.ai/
       license: Apache-2.0
diff --git a/conda/recipes/raft-ann-bench-cpu/conda_build_config.yaml b/conda/recipes/raft-ann-bench-cpu/conda_build_config.yaml
index 0bd424f85b..fda3e4e53d 100644
--- a/conda/recipes/raft-ann-bench-cpu/conda_build_config.yaml
+++ b/conda/recipes/raft-ann-bench-cpu/conda_build_config.yaml
@@ -18,3 +18,9 @@ h5py_version:
 
 nlohmann_json_version:
   - ">=3.11.2"
+
+spdlog_version:
+  - ">=1.11.0,<1.12"
+
+fmt_version:
+  - ">=9.1.0,<10"
diff --git a/conda/recipes/raft-ann-bench-cpu/meta.yaml b/conda/recipes/raft-ann-bench-cpu/meta.yaml
index 6db9400d97..fce85d5ffc 100644
--- a/conda/recipes/raft-ann-bench-cpu/meta.yaml
+++ b/conda/recipes/raft-ann-bench-cpu/meta.yaml
@@ -48,6 +48,8 @@ requirements:
     - glog {{ glog_version }}
     - matplotlib
     - nlohmann_json {{ nlohmann_json_version }}
+    - spdlog {{ spdlog_version }}
+    - fmt {{ fmt_version }}
     - python
     - pyyaml
     - pandas
diff --git a/cpp/bench/ann/src/raft/raft_ivf_flat_wrapper.h b/cpp/bench/ann/src/raft/raft_ivf_flat_wrapper.h
index 24b3c69bb6..13ea20d483 100644
--- a/cpp/bench/ann/src/raft/raft_ivf_flat_wrapper.h
+++ b/cpp/bench/ann/src/raft/raft_ivf_flat_wrapper.h
@@ -78,7 +78,7 @@ class RaftIvfFlatGpu : public ANN<T> {
   AlgoProperty get_preference() const override
   {
     AlgoProperty property;
-    property.dataset_memory_type = MemoryType::Device;
+    property.dataset_memory_type = MemoryType::HostMmap;
     property.query_memory_type   = MemoryType::Device;
     return property;
   }
diff --git a/cpp/include/raft/neighbors/detail/ivf_flat_build.cuh b/cpp/include/raft/neighbors/detail/ivf_flat_build.cuh
index a9a6ac025f..a35cb9e1f1 100644
--- a/cpp/include/raft/neighbors/detail/ivf_flat_build.cuh
+++ b/cpp/include/raft/neighbors/detail/ivf_flat_build.cuh
@@ -120,7 +120,8 @@ RAFT_KERNEL build_index_kernel(const LabelT* labels,
                                uint32_t* list_sizes_ptr,
                                IdxT n_rows,
                                uint32_t dim,
-                               uint32_t veclen)
+                               uint32_t veclen,
+                               IdxT batch_offset = 0)
 {
   const IdxT i = IdxT(blockDim.x) * IdxT(blockIdx.x) + threadIdx.x;
   if (i >= n_rows) { return; }
@@ -131,7 +132,7 @@ RAFT_KERNEL build_index_kernel(const LabelT* labels,
   auto* list_data  = list_data_ptrs[list_id];
 
   // Record the source vector id in the index
-  list_index[inlist_id] = source_ixs == nullptr ? i : source_ixs[i];
+  list_index[inlist_id] = source_ixs == nullptr ? i + batch_offset : source_ixs[i];
 
   // The data is written in interleaved groups of `index::kGroupSize` vectors
   using interleaved_group = Pow2<kIndexGroupSize>;
@@ -180,16 +181,33 @@ void extend(raft::resources const& handle,
 
   auto new_labels = raft::make_device_vector<LabelT, IdxT>(handle, n_rows);
   raft::cluster::kmeans_balanced_params kmeans_params;
-  kmeans_params.metric  = index->metric();
-  auto new_vectors_view = raft::make_device_matrix_view<const T, IdxT>(new_vectors, n_rows, dim);
+  kmeans_params.metric = index->metric();
   auto orig_centroids_view =
     raft::make_device_matrix_view<const float, IdxT>(index->centers().data_handle(), n_lists, dim);
-  raft::cluster::kmeans_balanced::predict(handle,
-                                          kmeans_params,
-                                          new_vectors_view,
-                                          orig_centroids_view,
-                                          new_labels.view(),
-                                          utils::mapping<float>{});
+  // Calculate the batch size for the input data if it's not accessible directly from the device
+  constexpr size_t kReasonableMaxBatchSize = 65536;
+  size_t max_batch_size                    = std::min<size_t>(n_rows, kReasonableMaxBatchSize);
+
+  // Predict the cluster labels for the new data, in batches if necessary
+  utils::batch_load_iterator<T> vec_batches(new_vectors,
+                                            n_rows,
+                                            index->dim(),
+                                            max_batch_size,
+                                            stream,
+                                            resource::get_workspace_resource(handle));
+
+  for (const auto& batch : vec_batches) {
+    auto batch_data_view =
+      raft::make_device_matrix_view<const T, IdxT>(batch.data(), batch.size(), index->dim());
+    auto batch_labels_view = raft::make_device_vector_view<LabelT, IdxT>(
+      new_labels.data_handle() + batch.offset(), batch.size());
+    raft::cluster::kmeans_balanced::predict(handle,
+                                            kmeans_params,
+                                            batch_data_view,
+                                            orig_centroids_view,
+                                            batch_labels_view,
+                                            utils::mapping<float>{});
+  }
 
   auto* list_sizes_ptr    = index->list_sizes().data_handle();
   auto old_list_sizes_dev = raft::make_device_vector<uint32_t, IdxT>(handle, n_lists);
@@ -202,14 +220,19 @@ void extend(raft::resources const& handle,
     auto list_sizes_view =
       raft::make_device_vector_view<std::remove_pointer_t<decltype(list_sizes_ptr)>, IdxT>(
         list_sizes_ptr, n_lists);
-    auto const_labels_view = make_const_mdspan(new_labels.view());
-    raft::cluster::kmeans_balanced::helpers::calc_centers_and_sizes(handle,
-                                                                    new_vectors_view,
-                                                                    const_labels_view,
-                                                                    centroids_view,
-                                                                    list_sizes_view,
-                                                                    false,
-                                                                    utils::mapping<float>{});
+    for (const auto& batch : vec_batches) {
+      auto batch_data_view =
+        raft::make_device_matrix_view<const T, IdxT>(batch.data(), batch.size(), index->dim());
+      auto batch_labels_view = raft::make_device_vector_view<const LabelT, IdxT>(
+        new_labels.data_handle() + batch.offset(), batch.size());
+      raft::cluster::kmeans_balanced::helpers::calc_centers_and_sizes(handle,
+                                                                      batch_data_view,
+                                                                      batch_labels_view,
+                                                                      centroids_view,
+                                                                      list_sizes_view,
+                                                                      false,
+                                                                      utils::mapping<float>{});
+    }
   } else {
     raft::stats::histogram<uint32_t, IdxT>(raft::stats::HistTypeAuto,
                                            reinterpret_cast<int32_t*>(list_sizes_ptr),
@@ -244,20 +267,39 @@ void extend(raft::resources const& handle,
   // we'll rebuild the `list_sizes_ptr` in the following kernel, using it as an atomic counter.
   raft::copy(list_sizes_ptr, old_list_sizes_dev.data_handle(), n_lists, stream);
 
-  // Kernel to insert the new vectors
-  const dim3 block_dim(256);
-  const dim3 grid_dim(raft::ceildiv<IdxT>(n_rows, block_dim.x));
-  build_index_kernel<<<grid_dim, block_dim, 0, stream>>>(new_labels.data_handle(),
-                                                         new_vectors,
-                                                         new_indices,
-                                                         index->data_ptrs().data_handle(),
-                                                         index->inds_ptrs().data_handle(),
-                                                         list_sizes_ptr,
-                                                         n_rows,
-                                                         dim,
-                                                         index->veclen());
-  RAFT_CUDA_TRY(cudaPeekAtLastError());
-
+  utils::batch_load_iterator<IdxT> vec_indices(
+    new_indices, n_rows, 1, max_batch_size, stream, resource::get_workspace_resource(handle));
+  utils::batch_load_iterator<IdxT> idx_batch = vec_indices.begin();
+  size_t next_report_offset                  = 0;
+  size_t d_report_offset                     = n_rows * 5 / 100;
+  for (const auto& batch : vec_batches) {
+    auto batch_data_view =
+      raft::make_device_matrix_view<const T, IdxT>(batch.data(), batch.size(), index->dim());
+    // Kernel to insert the new vectors
+    const dim3 block_dim(256);
+    const dim3 grid_dim(raft::ceildiv<IdxT>(batch.size(), block_dim.x));
+    build_index_kernel<T, IdxT, LabelT>
+      <<<grid_dim, block_dim, 0, stream>>>(new_labels.data_handle() + batch.offset(),
+                                           batch_data_view.data_handle(),
+                                           idx_batch->data(),
+                                           index->data_ptrs().data_handle(),
+                                           index->inds_ptrs().data_handle(),
+                                           list_sizes_ptr,
+                                           batch.size(),
+                                           dim,
+                                           index->veclen(),
+                                           batch.offset());
+    RAFT_CUDA_TRY(cudaPeekAtLastError());
+
+    if (batch.offset() > next_report_offset) {
+      float progress = batch.offset() * 100.0f / n_rows;
+      RAFT_LOG_DEBUG("ivf_flat::extend added vectors %zu, %6.1f%% complete",
+                     static_cast<size_t>(batch.offset()),
+                     progress);
+      next_report_offset += d_report_offset;
+    }
+    ++idx_batch;
+  }
   // Precompute the centers vector norms for L2Expanded distance
   if (!index->center_norms().has_value()) {
     index->allocate_center_norms(handle);
diff --git a/cpp/include/raft/neighbors/ivf_flat-ext.cuh b/cpp/include/raft/neighbors/ivf_flat-ext.cuh
index 8dbe7587ff..063105cf46 100644
--- a/cpp/include/raft/neighbors/ivf_flat-ext.cuh
+++ b/cpp/include/raft/neighbors/ivf_flat-ext.cuh
@@ -48,6 +48,18 @@ void build(raft::resources const& handle,
            raft::device_matrix_view<const T, IdxT, row_major> dataset,
            raft::neighbors::ivf_flat::index<T, IdxT>& idx) RAFT_EXPLICIT;
 
+template <typename T, typename IdxT>
+auto build(raft::resources const& handle,
+           const index_params& params,
+           raft::host_matrix_view<const T, IdxT, row_major> dataset)
+  -> index<T, IdxT> RAFT_EXPLICIT;
+
+template <typename T, typename IdxT>
+void build(raft::resources const& handle,
+           const index_params& params,
+           raft::host_matrix_view<const T, IdxT, row_major> dataset,
+           raft::neighbors::ivf_flat::index<T, IdxT>& idx) RAFT_EXPLICIT;
+
 template <typename T, typename IdxT>
 auto extend(raft::resources const& handle,
             const index<T, IdxT>& orig_index,
@@ -74,6 +86,19 @@ void extend(raft::resources const& handle,
             std::optional<raft::device_vector_view<const IdxT, IdxT>> new_indices,
             index<T, IdxT>* index) RAFT_EXPLICIT;
 
+template <typename T, typename IdxT>
+auto extend(raft::resources const& handle,
+            raft::host_matrix_view<const T, IdxT, row_major> new_vectors,
+            std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,
+            const raft::neighbors::ivf_flat::index<T, IdxT>& orig_index)
+  -> raft::neighbors::ivf_flat::index<T, IdxT> RAFT_EXPLICIT;
+
+template <typename T, typename IdxT>
+void extend(raft::resources const& handle,
+            raft::host_matrix_view<const T, IdxT, row_major> new_vectors,
+            std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,
+            index<T, IdxT>* index) RAFT_EXPLICIT;
+
 template <typename T, typename IdxT, typename IvfSampleFilterT>
 void search_with_filtering(raft::resources const& handle,
                            const search_params& params,
@@ -137,6 +162,18 @@ void search(raft::resources const& handle,
     raft::resources const& handle,                                \
     const raft::neighbors::ivf_flat::index_params& params,        \
     raft::device_matrix_view<const T, IdxT, row_major> dataset,   \
+    raft::neighbors::ivf_flat::index<T, IdxT>& idx);              \
+                                                                  \
+  extern template auto raft::neighbors::ivf_flat::build<T, IdxT>( \
+    raft::resources const& handle,                                \
+    const raft::neighbors::ivf_flat::index_params& params,        \
+    raft::host_matrix_view<const T, IdxT, row_major> dataset)     \
+    ->raft::neighbors::ivf_flat::index<T, IdxT>;                  \
+                                                                  \
+  extern template void raft::neighbors::ivf_flat::build<T, IdxT>( \
+    raft::resources const& handle,                                \
+    const raft::neighbors::ivf_flat::index_params& params,        \
+    raft::host_matrix_view<const T, IdxT, row_major> dataset,     \
     raft::neighbors::ivf_flat::index<T, IdxT>& idx);
 
 instantiate_raft_neighbors_ivf_flat_build(float, int64_t);
@@ -171,7 +208,20 @@ instantiate_raft_neighbors_ivf_flat_build(uint8_t, int64_t);
     raft::resources const& handle,                                         \
     raft::device_matrix_view<const T, IdxT, row_major> new_vectors,        \
     std::optional<raft::device_vector_view<const IdxT, IdxT>> new_indices, \
-    raft::neighbors::ivf_flat::index<T, IdxT>* index);
+    raft::neighbors::ivf_flat::index<T, IdxT>* index);                     \
+                                                                           \
+  extern template void raft::neighbors::ivf_flat::extend<T, IdxT>(         \
+    raft::resources const& handle,                                         \
+    raft::host_matrix_view<const T, IdxT, row_major> new_vectors,          \
+    std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,   \
+    raft::neighbors::ivf_flat::index<T, IdxT>* index);                     \
+                                                                           \
+  extern template auto raft::neighbors::ivf_flat::extend<T, IdxT>(         \
+    const raft::resources& handle,                                         \
+    raft::host_matrix_view<const T, IdxT, row_major> new_vectors,          \
+    std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,   \
+    const raft::neighbors::ivf_flat::index<T, IdxT>& idx)                  \
+    ->raft::neighbors::ivf_flat::index<T, IdxT>;
 
 instantiate_raft_neighbors_ivf_flat_extend(float, int64_t);
 instantiate_raft_neighbors_ivf_flat_extend(int8_t, int64_t);
diff --git a/cpp/include/raft/neighbors/ivf_flat-inl.cuh b/cpp/include/raft/neighbors/ivf_flat-inl.cuh
index 692fb08810..b540de7f14 100644
--- a/cpp/include/raft/neighbors/ivf_flat-inl.cuh
+++ b/cpp/include/raft/neighbors/ivf_flat-inl.cuh
@@ -55,7 +55,7 @@ namespace raft::neighbors::ivf_flat {
  *
  * @param[in] handle
  * @param[in] params configure the index building
- * @param[in] dataset a device pointer to a row-major matrix [n_rows, dim]
+ * @param[in] dataset a host or device pointer to a row-major matrix [n_rows, dim]
  * @param[in] n_rows the number of samples
  * @param[in] dim the dimensionality of the data
  *
@@ -102,7 +102,7 @@ auto build(raft::resources const& handle,
  *
  * @param[in] handle
  * @param[in] params configure the index building
- * @param[in] dataset a device pointer to a row-major matrix [n_rows, dim]
+ * @param[in] dataset a device matrix [n_rows, dim]
  *
  * @return the constructed ivf-flat index
  */
@@ -118,6 +118,20 @@ auto build(raft::resources const& handle,
                                                   static_cast<IdxT>(dataset.extent(1)));
 }
 
+/**
+ * @brief Build the index from a dataset in host memory.
+ */
+template <typename T, typename IdxT>
+auto build(raft::resources const& handle,
+           const index_params& params,
+           raft::host_matrix_view<const T, IdxT, row_major> dataset) -> index<T, IdxT>
+{
+  return raft::neighbors::ivf_flat::detail::build(handle,
+                                                  params,
+                                                  dataset.data_handle(),
+                                                  static_cast<IdxT>(dataset.extent(0)),
+                                                  static_cast<IdxT>(dataset.extent(1)));
+}
 /**
  * @brief Build the index from the dataset for efficient search.
  *
@@ -162,6 +176,21 @@ void build(raft::resources const& handle,
                                                  static_cast<IdxT>(dataset.extent(1)));
 }
 
+/**
+ * @brief Build the index from a dataset in host memory.
+ */
+template <typename T, typename IdxT>
+void build(raft::resources const& handle,
+           const index_params& params,
+           raft::host_matrix_view<const T, IdxT, row_major> dataset,
+           raft::neighbors::ivf_flat::index<T, IdxT>& idx)
+{
+  idx = raft::neighbors::ivf_flat::detail::build(handle,
+                                                 params,
+                                                 dataset.data_handle(),
+                                                 static_cast<IdxT>(dataset.extent(0)),
+                                                 static_cast<IdxT>(dataset.extent(1)));
+}
 /** @} */
 
 /**
@@ -188,8 +217,8 @@ void build(raft::resources const& handle,
  *
  * @param[in] handle
  * @param[in] orig_index original index
- * @param[in] new_vectors a device pointer to a row-major matrix [n_rows, index.dim()]
- * @param[in] new_indices a device pointer to a vector of indices [n_rows].
+ * @param[in] new_vectors a device/host pointer to a row-major matrix [n_rows, index.dim()]
+ * @param[in] new_indices a device/host pointer to a vector of indices [n_rows].
  *    If the original index is empty (`orig_index.size() == 0`), you can pass `nullptr`
  *    here to imply a continuous range `[0...n_rows)`.
  * @param[in] n_rows number of rows in `new_vectors`
@@ -257,6 +286,23 @@ auto extend(raft::resources const& handle,
                          new_vectors.extent(0));
 }
 
+/**
+ * @brief Extend the index with additional vectors.
+ *
+ * This overloads takes input data in host memory.
+ */
+template <typename T, typename IdxT>
+auto extend(raft::resources const& handle,
+            raft::host_matrix_view<const T, IdxT, row_major> new_vectors,
+            std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,
+            const index<T, IdxT>& orig_index) -> index<T, IdxT>
+{
+  return extend<T, IdxT>(handle,
+                         orig_index,
+                         new_vectors.data_handle(),
+                         new_indices.has_value() ? new_indices.value().data_handle() : nullptr,
+                         new_vectors.extent(0));
+}
 /** @} */
 
 /**
@@ -279,8 +325,8 @@ auto extend(raft::resources const& handle,
  *
  * @param handle
  * @param[inout] index
- * @param[in] new_vectors a device pointer to a row-major matrix [n_rows, index.dim()]
- * @param[in] new_indices a device pointer to a vector of indices [n_rows].
+ * @param[in] new_vectors a device/host pointer to a row-major matrix [n_rows, index.dim()]
+ * @param[in] new_indices a device/host pointer to a vector of indices [n_rows].
  *    If the original index is empty (`orig_index.size() == 0`), you can pass `nullptr`
  *    here to imply a continuous range `[0...n_rows)`.
  * @param[in] n_rows the number of samples
@@ -339,6 +385,23 @@ void extend(raft::resources const& handle,
          static_cast<IdxT>(new_vectors.extent(0)));
 }
 
+/**
+ * @brief Extend the index with additional vectors.
+ *
+ * This overloads takes input data in host memory.
+ */
+template <typename T, typename IdxT>
+void extend(raft::resources const& handle,
+            raft::host_matrix_view<const T, IdxT, row_major> new_vectors,
+            std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,
+            index<T, IdxT>* index)
+{
+  extend(handle,
+         index,
+         new_vectors.data_handle(),
+         new_indices.has_value() ? new_indices.value().data_handle() : nullptr,
+         static_cast<IdxT>(new_vectors.extent(0)));
+}
 /** @} */
 
 /**
diff --git a/cpp/src/neighbors/ivf_flat_00_generate.py b/cpp/src/neighbors/ivf_flat_00_generate.py
index b02606a23e..d987a4e17d 100644
--- a/cpp/src/neighbors/ivf_flat_00_generate.py
+++ b/cpp/src/neighbors/ivf_flat_00_generate.py
@@ -41,63 +41,88 @@
 """
 
 types = dict(
-    float_int64_t= ("float", "int64_t"),
+    float_int64_t=("float", "int64_t"),
     int8_t_int64_t=("int8_t", "int64_t"),
     uint8_t_int64_t=("uint8_t", "int64_t"),
 )
 
 build_macro = """
 #define instantiate_raft_neighbors_ivf_flat_build(T, IdxT)        \\
-  template auto raft::neighbors::ivf_flat::build<T, IdxT>( \\
-    raft::resources const& handle,                         \\
+  template auto raft::neighbors::ivf_flat::build<T, IdxT>(        \\
+    raft::resources const& handle,                                \\
     const raft::neighbors::ivf_flat::index_params& params,        \\
     const T* dataset,                                             \\
     IdxT n_rows,                                                  \\
     uint32_t dim)                                                 \\
     ->raft::neighbors::ivf_flat::index<T, IdxT>;                  \\
                                                                   \\
-  template auto raft::neighbors::ivf_flat::build<T, IdxT>( \\
-    raft::resources const& handle,                         \\
+  template auto raft::neighbors::ivf_flat::build<T, IdxT>(        \\
+    raft::resources const& handle,                                \\
     const raft::neighbors::ivf_flat::index_params& params,        \\
     raft::device_matrix_view<const T, IdxT, row_major> dataset)   \\
     ->raft::neighbors::ivf_flat::index<T, IdxT>;                  \\
                                                                   \\
-  template void raft::neighbors::ivf_flat::build<T, IdxT>( \\
-    raft::resources const& handle,                         \\
+  template void raft::neighbors::ivf_flat::build<T, IdxT>(        \\
+    raft::resources const& handle,                                \\
     const raft::neighbors::ivf_flat::index_params& params,        \\
     raft::device_matrix_view<const T, IdxT, row_major> dataset,   \\
+    raft::neighbors::ivf_flat::index<T, IdxT>& idx);              \\
+                                                                  \\
+  template auto raft::neighbors::ivf_flat::build<T, IdxT>(        \\
+    raft::resources const& handle,                                \\
+    const raft::neighbors::ivf_flat::index_params& params,        \\
+    raft::host_matrix_view<const T, IdxT, row_major> dataset)     \\
+    ->raft::neighbors::ivf_flat::index<T, IdxT>;                  \\
+                                                                  \\
+  template void raft::neighbors::ivf_flat::build<T, IdxT>(        \\
+    raft::resources const& handle,                                \\
+    const raft::neighbors::ivf_flat::index_params& params,        \\
+    raft::host_matrix_view<const T, IdxT, row_major> dataset,     \\
     raft::neighbors::ivf_flat::index<T, IdxT>& idx);
 """
 
 extend_macro = """
 #define instantiate_raft_neighbors_ivf_flat_extend(T, IdxT)                \\
-  template auto raft::neighbors::ivf_flat::extend<T, IdxT>(         \\
-    raft::resources const& handle,                                  \\
+  template auto raft::neighbors::ivf_flat::extend<T, IdxT>(                \\
+    raft::resources const& handle,                                         \\
     const raft::neighbors::ivf_flat::index<T, IdxT>& orig_index,           \\
     const T* new_vectors,                                                  \\
     const IdxT* new_indices,                                               \\
     IdxT n_rows)                                                           \\
     ->raft::neighbors::ivf_flat::index<T, IdxT>;                           \\
                                                                            \\
-  template auto raft::neighbors::ivf_flat::extend<T, IdxT>(         \\
-    raft::resources const& handle,                                  \\
+  template auto raft::neighbors::ivf_flat::extend<T, IdxT>(                \\
+    raft::resources const& handle,                                         \\
     raft::device_matrix_view<const T, IdxT, row_major> new_vectors,        \\
     std::optional<raft::device_vector_view<const IdxT, IdxT>> new_indices, \\
     const raft::neighbors::ivf_flat::index<T, IdxT>& orig_index)           \\
     ->raft::neighbors::ivf_flat::index<T, IdxT>;                           \\
                                                                            \\
-  template void raft::neighbors::ivf_flat::extend<T, IdxT>(         \\
-    raft::resources const& handle,                                  \\
+  template void raft::neighbors::ivf_flat::extend<T, IdxT>(                \\
+    raft::resources const& handle,                                         \\
     raft::neighbors::ivf_flat::index<T, IdxT>* index,                      \\
     const T* new_vectors,                                                  \\
     const IdxT* new_indices,                                               \\
     IdxT n_rows);                                                          \\
                                                                            \\
-  template void raft::neighbors::ivf_flat::extend<T, IdxT>(         \\
-    raft::resources const& handle,                                  \\
+  template void raft::neighbors::ivf_flat::extend<T, IdxT>(                \\
+    raft::resources const& handle,                                         \\
     raft::device_matrix_view<const T, IdxT, row_major> new_vectors,        \\
     std::optional<raft::device_vector_view<const IdxT, IdxT>> new_indices, \\
-    raft::neighbors::ivf_flat::index<T, IdxT>* index);
+    raft::neighbors::ivf_flat::index<T, IdxT>* index);                     \\
+                                                                           \\
+   template auto raft::neighbors::ivf_flat::extend<T, IdxT>(               \\
+    const raft::resources& handle,                                         \\
+    raft::host_matrix_view<const T, IdxT, row_major> new_vectors,          \\
+    std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,  \\
+    const raft::neighbors::ivf_flat::index<T, IdxT>& idx)                  \\
+    -> raft::neighbors::ivf_flat::index<T, IdxT>;                          \\
+                                                                           \\
+   template void raft::neighbors::ivf_flat::extend<T, IdxT>(               \\
+    raft::resources const& handle,                                         \\
+    raft::host_matrix_view<const T, IdxT, row_major> new_vectors,          \\
+    std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,   \\
+    raft::neighbors::ivf_flat::index<T, IdxT>* index);                     
 """
 
 search_macro = """
@@ -125,13 +150,16 @@
 macros = dict(
     build=dict(
         definition=build_macro,
-        name="instantiate_raft_neighbors_ivf_flat_build"),
+        name="instantiate_raft_neighbors_ivf_flat_build",
+    ),
     extend=dict(
         definition=extend_macro,
-        name="instantiate_raft_neighbors_ivf_flat_extend"),
+        name="instantiate_raft_neighbors_ivf_flat_extend",
+    ),
     search=dict(
         definition=search_macro,
-        name="instantiate_raft_neighbors_ivf_flat_search"),
+        name="instantiate_raft_neighbors_ivf_flat_search",
+    ),
 )
 
 for type_path, (T, IdxT) in types.items():
@@ -139,8 +167,7 @@
         path = f"ivf_flat_{macro_path}_{type_path}.cu"
         with open(path, "w") as f:
             f.write(header)
-            f.write(macro['definition'])
-
+            f.write(macro["definition"])
 
             f.write(f"{macro['name']}({T}, {IdxT});\n\n")
             f.write(f"#undef {macro['name']}\n")
diff --git a/cpp/src/neighbors/ivf_flat_build_float_int64_t.cu b/cpp/src/neighbors/ivf_flat_build_float_int64_t.cu
index 2ae795db56..cf3cb6b1b2 100644
--- a/cpp/src/neighbors/ivf_flat_build_float_int64_t.cu
+++ b/cpp/src/neighbors/ivf_flat_build_float_int64_t.cu
@@ -44,6 +44,18 @@
     raft::resources const& handle,                              \
     const raft::neighbors::ivf_flat::index_params& params,      \
     raft::device_matrix_view<const T, IdxT, row_major> dataset, \
+    raft::neighbors::ivf_flat::index<T, IdxT>& idx);            \
+                                                                \
+  template auto raft::neighbors::ivf_flat::build<T, IdxT>(      \
+    raft::resources const& handle,                              \
+    const raft::neighbors::ivf_flat::index_params& params,      \
+    raft::host_matrix_view<const T, IdxT, row_major> dataset)   \
+    ->raft::neighbors::ivf_flat::index<T, IdxT>;                \
+                                                                \
+  template void raft::neighbors::ivf_flat::build<T, IdxT>(      \
+    raft::resources const& handle,                              \
+    const raft::neighbors::ivf_flat::index_params& params,      \
+    raft::host_matrix_view<const T, IdxT, row_major> dataset,   \
     raft::neighbors::ivf_flat::index<T, IdxT>& idx);
 instantiate_raft_neighbors_ivf_flat_build(float, int64_t);
 
diff --git a/cpp/src/neighbors/ivf_flat_build_int8_t_int64_t.cu b/cpp/src/neighbors/ivf_flat_build_int8_t_int64_t.cu
index deb31bf441..e1cf64907e 100644
--- a/cpp/src/neighbors/ivf_flat_build_int8_t_int64_t.cu
+++ b/cpp/src/neighbors/ivf_flat_build_int8_t_int64_t.cu
@@ -44,6 +44,18 @@
     raft::resources const& handle,                              \
     const raft::neighbors::ivf_flat::index_params& params,      \
     raft::device_matrix_view<const T, IdxT, row_major> dataset, \
+    raft::neighbors::ivf_flat::index<T, IdxT>& idx);            \
+                                                                \
+  template auto raft::neighbors::ivf_flat::build<T, IdxT>(      \
+    raft::resources const& handle,                              \
+    const raft::neighbors::ivf_flat::index_params& params,      \
+    raft::host_matrix_view<const T, IdxT, row_major> dataset)   \
+    ->raft::neighbors::ivf_flat::index<T, IdxT>;                \
+                                                                \
+  template void raft::neighbors::ivf_flat::build<T, IdxT>(      \
+    raft::resources const& handle,                              \
+    const raft::neighbors::ivf_flat::index_params& params,      \
+    raft::host_matrix_view<const T, IdxT, row_major> dataset,   \
     raft::neighbors::ivf_flat::index<T, IdxT>& idx);
 instantiate_raft_neighbors_ivf_flat_build(int8_t, int64_t);
 
diff --git a/cpp/src/neighbors/ivf_flat_build_uint8_t_int64_t.cu b/cpp/src/neighbors/ivf_flat_build_uint8_t_int64_t.cu
index 402fdbab97..26d1647954 100644
--- a/cpp/src/neighbors/ivf_flat_build_uint8_t_int64_t.cu
+++ b/cpp/src/neighbors/ivf_flat_build_uint8_t_int64_t.cu
@@ -44,6 +44,18 @@
     raft::resources const& handle,                              \
     const raft::neighbors::ivf_flat::index_params& params,      \
     raft::device_matrix_view<const T, IdxT, row_major> dataset, \
+    raft::neighbors::ivf_flat::index<T, IdxT>& idx);            \
+                                                                \
+  template auto raft::neighbors::ivf_flat::build<T, IdxT>(      \
+    raft::resources const& handle,                              \
+    const raft::neighbors::ivf_flat::index_params& params,      \
+    raft::host_matrix_view<const T, IdxT, row_major> dataset)   \
+    ->raft::neighbors::ivf_flat::index<T, IdxT>;                \
+                                                                \
+  template void raft::neighbors::ivf_flat::build<T, IdxT>(      \
+    raft::resources const& handle,                              \
+    const raft::neighbors::ivf_flat::index_params& params,      \
+    raft::host_matrix_view<const T, IdxT, row_major> dataset,   \
     raft::neighbors::ivf_flat::index<T, IdxT>& idx);
 instantiate_raft_neighbors_ivf_flat_build(uint8_t, int64_t);
 
diff --git a/cpp/src/neighbors/ivf_flat_extend_float_int64_t.cu b/cpp/src/neighbors/ivf_flat_extend_float_int64_t.cu
index 9e7701f773..16472c6692 100644
--- a/cpp/src/neighbors/ivf_flat_extend_float_int64_t.cu
+++ b/cpp/src/neighbors/ivf_flat_extend_float_int64_t.cu
@@ -52,6 +52,19 @@
     raft::resources const& handle,                                         \
     raft::device_matrix_view<const T, IdxT, row_major> new_vectors,        \
     std::optional<raft::device_vector_view<const IdxT, IdxT>> new_indices, \
+    raft::neighbors::ivf_flat::index<T, IdxT>* index);                     \
+                                                                           \
+  template auto raft::neighbors::ivf_flat::extend<T, IdxT>(                \
+    const raft::resources& handle,                                         \
+    raft::host_matrix_view<const T, IdxT, row_major> new_vectors,          \
+    std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,   \
+    const raft::neighbors::ivf_flat::index<T, IdxT>& idx)                  \
+    ->raft::neighbors::ivf_flat::index<T, IdxT>;                           \
+                                                                           \
+  template void raft::neighbors::ivf_flat::extend<T, IdxT>(                \
+    raft::resources const& handle,                                         \
+    raft::host_matrix_view<const T, IdxT, row_major> new_vectors,          \
+    std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,   \
     raft::neighbors::ivf_flat::index<T, IdxT>* index);
 instantiate_raft_neighbors_ivf_flat_extend(float, int64_t);
 
diff --git a/cpp/src/neighbors/ivf_flat_extend_int8_t_int64_t.cu b/cpp/src/neighbors/ivf_flat_extend_int8_t_int64_t.cu
index 5d3d23c3ab..d98b5225c3 100644
--- a/cpp/src/neighbors/ivf_flat_extend_int8_t_int64_t.cu
+++ b/cpp/src/neighbors/ivf_flat_extend_int8_t_int64_t.cu
@@ -52,6 +52,19 @@
     raft::resources const& handle,                                         \
     raft::device_matrix_view<const T, IdxT, row_major> new_vectors,        \
     std::optional<raft::device_vector_view<const IdxT, IdxT>> new_indices, \
+    raft::neighbors::ivf_flat::index<T, IdxT>* index);                     \
+                                                                           \
+  template auto raft::neighbors::ivf_flat::extend<T, IdxT>(                \
+    const raft::resources& handle,                                         \
+    raft::host_matrix_view<const T, IdxT, row_major> new_vectors,          \
+    std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,   \
+    const raft::neighbors::ivf_flat::index<T, IdxT>& idx)                  \
+    ->raft::neighbors::ivf_flat::index<T, IdxT>;                           \
+                                                                           \
+  template void raft::neighbors::ivf_flat::extend<T, IdxT>(                \
+    raft::resources const& handle,                                         \
+    raft::host_matrix_view<const T, IdxT, row_major> new_vectors,          \
+    std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,   \
     raft::neighbors::ivf_flat::index<T, IdxT>* index);
 instantiate_raft_neighbors_ivf_flat_extend(int8_t, int64_t);
 
diff --git a/cpp/src/neighbors/ivf_flat_extend_uint8_t_int64_t.cu b/cpp/src/neighbors/ivf_flat_extend_uint8_t_int64_t.cu
index 3150a676eb..520c3be536 100644
--- a/cpp/src/neighbors/ivf_flat_extend_uint8_t_int64_t.cu
+++ b/cpp/src/neighbors/ivf_flat_extend_uint8_t_int64_t.cu
@@ -52,6 +52,19 @@
     raft::resources const& handle,                                         \
     raft::device_matrix_view<const T, IdxT, row_major> new_vectors,        \
     std::optional<raft::device_vector_view<const IdxT, IdxT>> new_indices, \
+    raft::neighbors::ivf_flat::index<T, IdxT>* index);                     \
+                                                                           \
+  template auto raft::neighbors::ivf_flat::extend<T, IdxT>(                \
+    const raft::resources& handle,                                         \
+    raft::host_matrix_view<const T, IdxT, row_major> new_vectors,          \
+    std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,   \
+    const raft::neighbors::ivf_flat::index<T, IdxT>& idx)                  \
+    ->raft::neighbors::ivf_flat::index<T, IdxT>;                           \
+                                                                           \
+  template void raft::neighbors::ivf_flat::extend<T, IdxT>(                \
+    raft::resources const& handle,                                         \
+    raft::host_matrix_view<const T, IdxT, row_major> new_vectors,          \
+    std::optional<raft::host_vector_view<const IdxT, IdxT>> new_indices,   \
     raft::neighbors::ivf_flat::index<T, IdxT>* index);
 instantiate_raft_neighbors_ivf_flat_extend(uint8_t, int64_t);
 
diff --git a/cpp/test/neighbors/ann_ivf_flat.cuh b/cpp/test/neighbors/ann_ivf_flat.cuh
index a9fd696f1f..39439d392d 100644
--- a/cpp/test/neighbors/ann_ivf_flat.cuh
+++ b/cpp/test/neighbors/ann_ivf_flat.cuh
@@ -72,6 +72,7 @@ struct AnnIvfFlatInputs {
   IdxT nlist;
   raft::distance::DistanceType metric;
   bool adaptive_centers;
+  bool host_dataset;
 };
 
 template <typename IdxT>
@@ -79,7 +80,7 @@ template <typename IdxT>
 {
   os << "{ " << p.num_queries << ", " << p.num_db_vecs << ", " << p.dim << ", " << p.k << ", "
      << p.nprobe << ", " << p.nlist << ", " << static_cast<int>(p.metric) << ", "
-     << p.adaptive_centers << '}' << std::endl;
+     << p.adaptive_centers << ", " << p.host_dataset << '}' << std::endl;
   return os;
 }
 
@@ -178,36 +179,69 @@ class AnnIVFFlatTest : public ::testing::TestWithParam<AnnIvfFlatInputs<IdxT>> {
         index_params.kmeans_trainset_fraction = 0.5;
         index_params.metric_arg               = 0;
 
-        auto database_view = raft::make_device_matrix_view<const DataT, IdxT>(
-          (const DataT*)database.data(), ps.num_db_vecs, ps.dim);
-
-        auto idx = ivf_flat::build(handle_, index_params, database_view);
+        ivf_flat::index<DataT, IdxT> idx(handle_, index_params, ps.dim);
+        ivf_flat::index<DataT, IdxT> index_2(handle_, index_params, ps.dim);
+
+        if (!ps.host_dataset) {
+          auto database_view = raft::make_device_matrix_view<const DataT, IdxT>(
+            (const DataT*)database.data(), ps.num_db_vecs, ps.dim);
+          idx = ivf_flat::build(handle_, index_params, database_view);
+          rmm::device_uvector<IdxT> vector_indices(ps.num_db_vecs, stream_);
+          thrust::sequence(resource::get_thrust_policy(handle_),
+                           thrust::device_pointer_cast(vector_indices.data()),
+                           thrust::device_pointer_cast(vector_indices.data() + ps.num_db_vecs));
+          resource::sync_stream(handle_);
 
-        rmm::device_uvector<IdxT> vector_indices(ps.num_db_vecs, stream_);
-        thrust::sequence(resource::get_thrust_policy(handle_),
-                         thrust::device_pointer_cast(vector_indices.data()),
-                         thrust::device_pointer_cast(vector_indices.data() + ps.num_db_vecs));
-        resource::sync_stream(handle_);
+          IdxT half_of_data = ps.num_db_vecs / 2;
 
-        IdxT half_of_data = ps.num_db_vecs / 2;
+          auto half_of_data_view = raft::make_device_matrix_view<const DataT, IdxT>(
+            (const DataT*)database.data(), half_of_data, ps.dim);
 
-        auto half_of_data_view = raft::make_device_matrix_view<const DataT, IdxT>(
-          (const DataT*)database.data(), half_of_data, ps.dim);
+          const std::optional<raft::device_vector_view<const IdxT, IdxT>> no_opt = std::nullopt;
+          index_2 = ivf_flat::extend(handle_, half_of_data_view, no_opt, idx);
 
-        const std::optional<raft::device_vector_view<const IdxT, IdxT>> no_opt = std::nullopt;
-        index<DataT, IdxT> index_2 = ivf_flat::extend(handle_, half_of_data_view, no_opt, idx);
+          auto new_half_of_data_view = raft::make_device_matrix_view<const DataT, IdxT>(
+            database.data() + half_of_data * ps.dim, IdxT(ps.num_db_vecs) - half_of_data, ps.dim);
 
-        auto new_half_of_data_view = raft::make_device_matrix_view<const DataT, IdxT>(
-          database.data() + half_of_data * ps.dim, IdxT(ps.num_db_vecs) - half_of_data, ps.dim);
+          auto new_half_of_data_indices_view = raft::make_device_vector_view<const IdxT, IdxT>(
+            vector_indices.data() + half_of_data, IdxT(ps.num_db_vecs) - half_of_data);
 
-        auto new_half_of_data_indices_view = raft::make_device_vector_view<const IdxT, IdxT>(
-          vector_indices.data() + half_of_data, IdxT(ps.num_db_vecs) - half_of_data);
+          ivf_flat::extend(handle_,
+                           new_half_of_data_view,
+                           std::make_optional<raft::device_vector_view<const IdxT, IdxT>>(
+                             new_half_of_data_indices_view),
+                           &index_2);
 
-        ivf_flat::extend(handle_,
-                         new_half_of_data_view,
-                         std::make_optional<raft::device_vector_view<const IdxT, IdxT>>(
-                           new_half_of_data_indices_view),
-                         &index_2);
+        } else {
+          auto host_database = raft::make_host_matrix<DataT, IdxT>(ps.num_db_vecs, ps.dim);
+          raft::copy(
+            host_database.data_handle(), database.data(), ps.num_db_vecs * ps.dim, stream_);
+          idx =
+            ivf_flat::build(handle_, index_params, raft::make_const_mdspan(host_database.view()));
+
+          auto vector_indices = raft::make_host_vector<IdxT>(handle_, ps.num_db_vecs);
+          std::iota(vector_indices.data_handle(), vector_indices.data_handle() + ps.num_db_vecs, 0);
+
+          IdxT half_of_data = ps.num_db_vecs / 2;
+
+          auto half_of_data_view = raft::make_host_matrix_view<const DataT, IdxT>(
+            (const DataT*)host_database.data_handle(), half_of_data, ps.dim);
+
+          const std::optional<raft::host_vector_view<const IdxT, IdxT>> no_opt = std::nullopt;
+          index_2 = ivf_flat::extend(handle_, half_of_data_view, no_opt, idx);
+
+          auto new_half_of_data_view = raft::make_host_matrix_view<const DataT, IdxT>(
+            host_database.data_handle() + half_of_data * ps.dim,
+            IdxT(ps.num_db_vecs) - half_of_data,
+            ps.dim);
+          auto new_half_of_data_indices_view = raft::make_host_vector_view<const IdxT, IdxT>(
+            vector_indices.data_handle() + half_of_data, IdxT(ps.num_db_vecs) - half_of_data);
+          ivf_flat::extend(handle_,
+                           new_half_of_data_view,
+                           std::make_optional<raft::host_vector_view<const IdxT, IdxT>>(
+                             new_half_of_data_indices_view),
+                           &index_2);
+        }
 
         auto search_queries_view = raft::make_device_matrix_view<const DataT, IdxT>(
           search_queries.data(), ps.num_queries, ps.dim);
@@ -574,6 +608,15 @@ const std::vector<AnnIvfFlatInputs<int64_t>> inputs = {
   {1000, 100000, 16, 10, 20, 1024, raft::distance::DistanceType::L2Expanded, true},
   {10000, 131072, 8, 10, 20, 1024, raft::distance::DistanceType::L2Expanded, false},
 
+  // host input data
+  {1000, 10000, 16, 10, 40, 1024, raft::distance::DistanceType::L2Expanded, false, true},
+  {1000, 10000, 16, 10, 50, 1024, raft::distance::DistanceType::L2Expanded, false, true},
+  {1000, 10000, 16, 10, 70, 1024, raft::distance::DistanceType::L2Expanded, false, true},
+  {100, 10000, 16, 10, 20, 512, raft::distance::DistanceType::L2Expanded, false, true},
+  {20, 100000, 16, 10, 20, 1024, raft::distance::DistanceType::L2Expanded, false, true},
+  {1000, 100000, 16, 10, 20, 1024, raft::distance::DistanceType::L2Expanded, false, true},
+  {10000, 131072, 8, 10, 20, 1024, raft::distance::DistanceType::L2Expanded, false, true},
+
   {1000, 10000, 16, 10, 40, 1024, raft::distance::DistanceType::InnerProduct, true},
   {1000, 10000, 16, 10, 50, 1024, raft::distance::DistanceType::InnerProduct, true},
   {1000, 10000, 16, 10, 70, 1024, raft::distance::DistanceType::InnerProduct, false},