diff --git a/CHANGELOG.md b/CHANGELOG.md
index 572ff4a0..96a92565 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,8 @@ adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ADDED
 
+- Added `OrchestrationQuery.instance_id_prefix` to retrieve orchestration
+instances whose IDs begin with a specified prefix.
 - Added the optional `new_version` argument to
 `OrchestrationContext.continue_as_new()` so continued orchestrations can
 switch to a new version.
diff --git a/azure-functions-durable/CHANGELOG.md b/azure-functions-durable/CHANGELOG.md
index f5e4adf3..4d19faec 100644
--- a/azure-functions-durable/CHANGELOG.md
+++ b/azure-functions-durable/CHANGELOG.md
@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+ADDED
+
+- Added inherited `OrchestrationQuery.instance_id_prefix` support to retrieve
+orchestration instances whose IDs begin with a specified prefix.
+
 ## v2.0.0b2
 
 ADDED
diff --git a/durabletask-azuremanaged/CHANGELOG.md b/durabletask-azuremanaged/CHANGELOG.md
index dde10137..6e671cd1 100644
--- a/durabletask-azuremanaged/CHANGELOG.md
+++ b/durabletask-azuremanaged/CHANGELOG.md
@@ -7,6 +7,11 @@ adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## Unreleased
 
+ADDED
+
+- Added inherited `OrchestrationQuery.instance_id_prefix` support to retrieve
+orchestration instances whose IDs begin with a specified prefix.
+
 ## v1.9.0
 
 CHANGED
diff --git a/durabletask/client.py b/durabletask/client.py
index a5974749..b88df604 100644
--- a/durabletask/client.py
+++ b/durabletask/client.py
@@ -196,6 +196,7 @@ class OrchestrationQuery:
     # results instead.
     max_instance_count: int | None = (1 << 31) - 1
     fetch_inputs_and_outputs: bool = False
+    instance_id_prefix: str | None = None
 
 
 @dataclass
diff --git a/durabletask/internal/client_helpers.py b/durabletask/internal/client_helpers.py
index fe0c828b..d3c51181 100644
--- a/durabletask/internal/client_helpers.py
+++ b/durabletask/internal/client_helpers.py
@@ -103,6 +103,7 @@ def build_query_instances_req(
             runtimeStatus=[status.value for status in orchestration_query.runtime_status] if orchestration_query.runtime_status else None,
             createdTimeFrom=helpers.new_timestamp(orchestration_query.created_time_from) if orchestration_query.created_time_from else None,
             createdTimeTo=helpers.new_timestamp(orchestration_query.created_time_to) if orchestration_query.created_time_to else None,
+            instanceIdPrefix=helpers.get_string_value(orchestration_query.instance_id_prefix),
             maxInstanceCount=orchestration_query.max_instance_count,
             fetchInputsAndOutputs=orchestration_query.fetch_inputs_and_outputs,
             continuationToken=continuation_token
diff --git a/tests/durabletask/test_batch_actions.py b/tests/durabletask/test_batch_actions.py
index 65637df0..24989746 100644
--- a/tests/durabletask/test_batch_actions.py
+++ b/tests/durabletask/test_batch_actions.py
@@ -12,6 +12,7 @@
 import pytest
 from durabletask import client, entities, task
 from durabletask.client import TaskHubGrpcClient
+from durabletask.internal.client_helpers import build_query_instances_req
 from durabletask.testing import create_test_backend
 from durabletask.worker import TaskHubGrpcWorker
 
@@ -163,6 +164,47 @@ def test_get_orchestration_state_by_time_range(backend):
     assert len([o for o in orchestrations_outside_range if o.instance_id == id]) == 0
 
 
+def test_get_orchestration_state_by_instance_id_prefix(backend):
+    worker = TaskHubGrpcWorker(host_address=HOST)
+
+    worker.add_orchestrator(empty_orchestrator)
+    worker.start()
+
+    try:
+        with TaskHubGrpcClient(host_address=HOST) as c:
+            matching_id = "prefix-match"
+            non_matching_id = "other-instance"
+            c.schedule_new_orchestration(empty_orchestrator, instance_id=matching_id)
+            c.schedule_new_orchestration(empty_orchestrator, instance_id=non_matching_id)
+            c.wait_for_orchestration_completion(matching_id, timeout=30)
+            c.wait_for_orchestration_completion(non_matching_id, timeout=30)
+
+            query = client.OrchestrationQuery(instance_id_prefix="prefix-")
+            orchestrations = c.get_all_orchestration_states(query)
+    finally:
+        worker.stop()
+
+    assert [orchestration.instance_id for orchestration in orchestrations] == [matching_id]
+
+
+def test_orchestration_query_serializes_instance_id_prefix():
+    request = build_query_instances_req(
+        client.OrchestrationQuery(instance_id_prefix="prefix-"),
+        continuation_token=None,
+    )
+
+    assert request.query.HasField("instanceIdPrefix")
+    assert request.query.instanceIdPrefix.value == "prefix-"
+
+
+def test_orchestration_query_preserves_positional_argument_order():
+    query = client.OrchestrationQuery(None, None, None, None, True)
+
+    assert query.max_instance_count is None
+    assert query.fetch_inputs_and_outputs is True
+    assert query.instance_id_prefix is None
+
+
 def test_get_orchestration_state_pagination_succeeds(backend):
     # Create a custom handler to capture log messages
     log_records = []