diff --git a/src/dapla_pseudo/v1/depseudo.py b/src/dapla_pseudo/v1/depseudo.py
index 7c219b70..022506ca 100644
--- a/src/dapla_pseudo/v1/depseudo.py
+++ b/src/dapla_pseudo/v1/depseudo.py
@@ -4,6 +4,7 @@
 import typing as t
 from concurrent.futures import ThreadPoolExecutor
 from concurrent.futures import as_completed
+from datetime import date
 from typing import Optional
 
 import pandas as pd
@@ -14,10 +15,12 @@
 from dapla_pseudo.constants import PredefinedKeys
 from dapla_pseudo.constants import PseudoFunctionTypes
 from dapla_pseudo.types import FileLikeDatasetDecl
+from dapla_pseudo.utils import convert_to_date
 from dapla_pseudo.v1.api_models import DaeadKeywordArgs
 from dapla_pseudo.v1.api_models import DepseudonymizeFileRequest
 from dapla_pseudo.v1.api_models import FF31KeywordArgs
 from dapla_pseudo.v1.api_models import KeyWrapper
+from dapla_pseudo.v1.api_models import MapSidKeywordArgs
 from dapla_pseudo.v1.api_models import Mimetypes
 from dapla_pseudo.v1.api_models import PseudoConfig
 from dapla_pseudo.v1.api_models import PseudoFunction
@@ -231,6 +234,38 @@ def __init__(
             self._fields = fields
             self._existing_rules = [] if rules is None else rules
 
+        def with_stable_id(
+            self,
+            sid_snapshot_date: Optional[str | date] = None,
+            custom_key: Optional[str] = None,
+        ) -> "Depseudonymize._Depseudonymizer":
+            """Depseudonymize the selected fields with the default encryption algorithm (DAEAD).
+
+            1) Decrypt stable-id
+            2) Then map decrypted stable-id to fnr and return original fnr.
+
+            Args:
+                sid_snapshot_date (Optional[str | date], optional): Date representing SID-catalogue version to use.
+                    Latest if unspecified. Format: YYYY-MM-DD
+                custom_key (Optional[PredefinedKeys | str], optional): Override the key to use for pseudonymization.
+                    Must be one of the keys defined in PredefinedKeys. If not defined, uses the default key for this function (papis-common-key-1)
+
+            Returns:
+                Self: The object configured to be mapped to fnr
+            """
+            kwargs = (
+                MapSidKeywordArgs(
+                    key_id=custom_key,
+                    snapshot_date=convert_to_date(sid_snapshot_date),
+                )
+                if custom_key
+                else MapSidKeywordArgs(snapshot_date=convert_to_date(sid_snapshot_date))
+            )
+            function = PseudoFunction(
+                function_type=PseudoFunctionTypes.MAP_SID, kwargs=kwargs
+            )
+            return self._rule_constructor(function)
+
         def with_default_encryption(
             self, custom_key: Optional[PredefinedKeys | str] = None
         ) -> "Depseudonymize._Depseudonymizer":
diff --git a/tests/conftest.py b/tests/conftest.py
index b5126420..9a28344f 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -70,6 +70,36 @@ def df_personer_fnr_daead_encrypted() -> pl.DataFrame:
     )
 
 
+@pytest.fixture
+def df_personer_pseudo_stable_id() -> pl.DataFrame:
+    JSON_FILE = "tests/data/person_3_sid_deid.json"
+    return pl.read_json(
+        JSON_FILE,
+        schema={
+            "fnr": pl.String,
+            "fornavn": pl.String,
+            "etternavn": pl.String,
+            "kjonn": pl.String,
+            "fodselsdato": pl.String,
+        },
+    )
+
+
+@pytest.fixture
+def df_personer_depseudo_stable_id() -> pl.DataFrame:
+    JSON_FILE = "tests/data/person_3_sid.json"
+    return pl.read_json(
+        JSON_FILE,
+        schema={
+            "fnr": pl.String,
+            "fornavn": pl.String,
+            "etternavn": pl.String,
+            "kjonn": pl.String,
+            "fodselsdato": pl.String,
+        },
+    )
+
+
 @pytest.fixture
 def df_pandas_personer_fnr_daead_encrypted() -> pd.DataFrame:
     JSON_FILE = "tests/data/personer_pseudonymized_default_encryption.json"
diff --git a/tests/data/person_3_sid.json b/tests/data/person_3_sid.json
new file mode 100644
index 00000000..77882da5
--- /dev/null
+++ b/tests/data/person_3_sid.json
@@ -0,0 +1,23 @@
+[
+  {
+    "fnr": "11854898347",
+    "fornavn": "Mathias",
+    "etternavn": "Holm",
+    "kjonn": "M",
+    "fodselsdato": "020995"
+  },
+  {
+    "fnr": "01839899544",
+    "fornavn": "Gunnar",
+    "etternavn": "Jørgensen",
+    "kjonn": "M",
+    "fodselsdato": "060970"
+  },
+  {
+    "fnr": "02812289295",
+    "fornavn": "Kristoffer",
+    "etternavn": "Pedersen",
+    "kjonn": "M",
+    "fodselsdato": "180999"
+  }
+]
diff --git a/tests/data/person_3_sid_deid.json b/tests/data/person_3_sid_deid.json
new file mode 100644
index 00000000..ba919696
--- /dev/null
+++ b/tests/data/person_3_sid_deid.json
@@ -0,0 +1,23 @@
+[
+  {
+    "fnr": "jJuuj0i",
+    "fornavn": "Mathias",
+    "etternavn": "Holm",
+    "kjonn": "M",
+    "fodselsdato": "020995"
+  },
+  {
+    "fnr": "ylc9488",
+    "fornavn": "Gunnar",
+    "etternavn": "Jørgensen",
+    "kjonn": "M",
+    "fodselsdato": "060970"
+  },
+  {
+    "fnr": "mprMeNQ",
+    "fornavn": "Kristoffer",
+    "etternavn": "Pedersen",
+    "kjonn": "M",
+    "fodselsdato": "180999"
+  }
+]
diff --git a/tests/integration/test_integration_deseudonymize.py b/tests/integration/test_integration_deseudonymize.py
index 17a313b9..ac679be3 100644
--- a/tests/integration/test_integration_deseudonymize.py
+++ b/tests/integration/test_integration_deseudonymize.py
@@ -21,3 +21,20 @@ def test_depseudonymize_default_encryption(
         .to_polars()
     )
     assert result.equals(df_personer)
+
+
+@integration_test()
+def test_depseudonymize_sid(
+    setup: Generator[None, None, None],
+    df_personer: pl.DataFrame,
+    df_personer_pseudo_stable_id: pl.DataFrame,
+    df_personer_depseudo_stable_id: pl.DataFrame,
+) -> None:
+    result = (
+        Depseudonymize.from_polars(df_personer_pseudo_stable_id)
+        .on_fields("fnr")
+        .with_stable_id()
+        .run()
+        .to_polars()
+    )
+    assert result.equals(df_personer_depseudo_stable_id)
diff --git a/tests/v1/test_depseudo.py b/tests/v1/test_depseudo.py
index 12a869f0..66417c99 100644
--- a/tests/v1/test_depseudo.py
+++ b/tests/v1/test_depseudo.py
@@ -116,6 +116,25 @@ def test_builder_fields_selector_multiple_fields(
     ]
 
 
+@patch(f"{PKG}.pseudonymize_operation_field")
+def test_builder_depseudo_function_selector_with_sid(
+    patch_depseudonymize_operation_field: MagicMock, df_personer: pl.DataFrame
+) -> None:
+    mock_return_pseudonymize_operation_field(patch_depseudonymize_operation_field)
+    Depseudonymize.from_polars(df_personer).on_fields("fnr").with_stable_id().run()
+    patch_depseudonymize_operation_field.assert_called_once_with(
+        path="depseudonymize/field",
+        values=df_personer["fnr"].to_list(),
+        field_name="fnr",
+        pseudo_func=PseudoFunction(
+            function_type=PseudoFunctionTypes.MAP_SID, kwargs=MapSidKeywordArgs()
+        ),
+        timeout=TIMEOUT_DEFAULT,
+        pseudo_client=ANY,
+        keyset=None,
+    )
+
+
 @patch(f"{PKG}.pseudo_operation_file")
 def test_builder_file_default(
     patched_pseudo_operation_file: MagicMock, personer_pseudonymized_file_path: str