diff --git a/src/AttestationRegistry.sol b/src/AttestationRegistry.sol
index f0a922f2..57176b7e 100644
--- a/src/AttestationRegistry.sol
+++ b/src/AttestationRegistry.sol
@@ -2,6 +2,7 @@
 pragma solidity 0.8.21;
 
 import { OwnableUpgradeable } from "openzeppelin-contracts-upgradeable/contracts/access/OwnableUpgradeable.sol";
+import { ERC1155Upgradeable } from "openzeppelin-contracts-upgradeable/contracts/token/ERC1155/ERC1155Upgradeable.sol";
 import { Attestation, AttestationPayload } from "./types/Structs.sol";
 import { PortalRegistry } from "./PortalRegistry.sol";
 import { SchemaRegistry } from "./SchemaRegistry.sol";
@@ -12,7 +13,7 @@ import { IRouter } from "./interface/IRouter.sol";
  * @author Consensys
  * @notice This contract stores a registry of all attestations
  */
-contract AttestationRegistry is OwnableUpgradeable {
+contract AttestationRegistry is OwnableUpgradeable, ERC1155Upgradeable {
   IRouter public router;
 
   uint16 private version;
@@ -262,4 +263,37 @@ contract AttestationRegistry is OwnableUpgradeable {
   function getAttestationIdCounter() public view returns (uint32) {
     return attestationIdCounter;
   }
+
+  /**
+   * @notice Checks if an address owns a given attestation
+   * @param account The address of the token holder
+   * @param id ID of the attestation
+   * @return The _owner's balance of the attestations on a given attestation ID
+   */
+  function balanceOf(address account, uint256 id) public view override returns (uint256) {
+    bytes32 attestationId = bytes32(abi.encode(id));
+    Attestation memory attestation = attestations[attestationId];
+    if (keccak256(attestation.subject) == keccak256(abi.encode(account))) return 1;
+    return 0;
+  }
+
+  /**
+   * @notice Get the balance of multiple account/attestation pairs
+   * @param accounts The addresses of the attestation holders
+   * @param ids ID of the attestations
+   * @return The _owner's balance of the attestation for a given address (i.e. balance for each (owner, id) pair)
+   */
+  function balanceOfBatch(
+    address[] memory accounts,
+    uint256[] memory ids
+  ) public view override returns (uint256[] memory) {
+    if (accounts.length != ids.length) revert ArrayLengthMismatch();
+    uint256[] memory result = new uint256[](accounts.length);
+    for (uint256 i = 0; i < accounts.length; i++) {
+      bytes32 attestationId = bytes32(abi.encode(ids[i]));
+      Attestation memory attestation = attestations[attestationId];
+      if (keccak256(attestation.subject) == keccak256(abi.encode(accounts[i]))) result[i] = 1;
+    }
+    return result;
+  }
 }
diff --git a/test/AttestationRegistry.t.sol b/test/AttestationRegistry.t.sol
index f6d3f1b2..88ac3085 100644
--- a/test/AttestationRegistry.t.sol
+++ b/test/AttestationRegistry.t.sol
@@ -484,25 +484,76 @@ contract AttestationRegistryTest is Test {
     SchemaRegistryMock schemaRegistryMock = SchemaRegistryMock(router.getSchemaRegistry());
     attestationPayload.schemaId = schemaRegistryMock.getIdFromSchemaString("schemaString");
     schemaRegistryMock.createSchema("name", "description", "context", "schemaString");
-    uint32 version = attestationRegistry.getAttestationIdCounter();
+    uint32 attestationIdCounter = attestationRegistry.getAttestationIdCounter();
 
-    assertEq(version, 0);
+    assertEq(attestationIdCounter, 0);
 
     vm.startPrank(portal);
 
     attestationRegistry.attest(attestationPayload, attester);
 
-    version = attestationRegistry.getAttestationIdCounter();
-    assertEq(version, 1);
+    attestationIdCounter = attestationRegistry.getAttestationIdCounter();
+    assertEq(attestationIdCounter, 1);
 
     attestationRegistry.attest(attestationPayload, attester);
 
-    version = attestationRegistry.getAttestationIdCounter();
-    assertEq(version, 2);
+    attestationIdCounter = attestationRegistry.getAttestationIdCounter();
+    assertEq(attestationIdCounter, 2);
 
     vm.stopPrank();
   }
 
+  function test_balanceOf(AttestationPayload memory attestationPayload) public {
+    vm.assume(attestationPayload.subject.length != 0);
+    vm.assume(attestationPayload.attestationData.length != 0);
+    SchemaRegistryMock schemaRegistryMock = SchemaRegistryMock(router.getSchemaRegistry());
+    attestationPayload.schemaId = schemaRegistryMock.getIdFromSchemaString("schemaString");
+    schemaRegistryMock.createSchema("name", "description", "context", "schemaString");
+
+    vm.startPrank(portal);
+    attestationPayload.subject = abi.encode(address(1));
+    attestationRegistry.attest(attestationPayload, attester);
+
+    uint256 balance = attestationRegistry.balanceOf(address(1), 1);
+    assertEq(balance, 1);
+  }
+
+  function test_balanceOfBatch(AttestationPayload memory attestationPayload) public {
+    vm.assume(attestationPayload.subject.length != 0);
+    vm.assume(attestationPayload.attestationData.length != 0);
+    SchemaRegistryMock schemaRegistryMock = SchemaRegistryMock(router.getSchemaRegistry());
+    attestationPayload.schemaId = schemaRegistryMock.getIdFromSchemaString("schemaString");
+    schemaRegistryMock.createSchema("name", "description", "context", "schemaString");
+
+    address[] memory owners = new address[](2);
+    owners[0] = address(1);
+    owners[1] = address(2);
+
+    vm.startPrank(portal);
+    attestationPayload.subject = abi.encode(owners[0]);
+    attestationRegistry.attest(attestationPayload, attester);
+
+    attestationPayload.subject = abi.encode(owners[1]);
+    attestationRegistry.attest(attestationPayload, attester);
+
+    uint256[] memory ids = new uint256[](2);
+    ids[0] = 1;
+    ids[1] = 2;
+    uint256[] memory balance = attestationRegistry.balanceOfBatch(owners, ids);
+    assertEq(balance[0], 1);
+    assertEq(balance[1], 1);
+  }
+
+  function test_balanceOfBatch_ArrayLengthMismatch() public {
+    address[] memory owners = new address[](2);
+    owners[0] = address(1);
+    owners[1] = address(2);
+    uint256[] memory ids = new uint256[](1);
+    ids[0] = 1;
+    vm.expectRevert(AttestationRegistry.ArrayLengthMismatch.selector);
+    attestationRegistry.balanceOfBatch(owners, ids);
+  }
+
   function _createAttestation(
     AttestationPayload memory attestationPayload,
     uint256 id