diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8602fba5..8f392131 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
 
+### Added
+
+- Added support for Collections search
+
 ### Changed
 
 - updated `numReturned` & `numMatched` fields in itemCollection return to `numberReturned` & `numberMatched`. [#446](https://github.com/stac-utils/stac-fastapi-elasticsearch-opensearch/pull/446)
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/app.py b/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/app.py
index 6e046044..248d2c1f 100644
--- a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/app.py
+++ b/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/app.py
@@ -37,6 +37,7 @@
 from stac_fastapi.extensions.core import (
     AggregationExtension,
     CollectionSearchExtension,
+    CollectionSearchFilterExtension,
     FilterExtension,
     FreeTextExtension,
     SortExtension,
@@ -45,6 +46,7 @@
 )
 from stac_fastapi.extensions.core.fields import FieldsConformanceClasses
 from stac_fastapi.extensions.core.filter import FilterConformanceClasses
+from stac_fastapi.extensions.core.free_text import FreeTextConformanceClasses
 from stac_fastapi.extensions.core.query import QueryConformanceClasses
 from stac_fastapi.extensions.core.sort import SortConformanceClasses
 from stac_fastapi.extensions.third_party import BulkTransactionExtension
@@ -86,6 +88,7 @@
 aggregation_extension.POST = EsAggregationExtensionPostRequest
 aggregation_extension.GET = EsAggregationExtensionGetRequest
 
+# Base search extensions (without CollectionSearchExtension to avoid duplicates)
 fields_extension = FieldsExtension()
 fields_extension.conformance_classes.append(FieldsConformanceClasses.ITEMS)
 
@@ -120,8 +123,29 @@
         ),
     )
 
+# Initialize extensions with just the search and aggregation extensions
+# Initialize with base extensions
 extensions = [aggregation_extension] + search_extensions
 
+# Create collection search extensions
+collection_search_extensions = [
+    QueryExtension(conformance_classes=[QueryConformanceClasses.COLLECTIONS]),
+    SortExtension(conformance_classes=[SortConformanceClasses.COLLECTIONS]),
+    FieldsExtension(conformance_classes=[FieldsConformanceClasses.COLLECTIONS]),
+    CollectionSearchFilterExtension(
+        conformance_classes=[FilterConformanceClasses.COLLECTIONS]
+    ),
+    FreeTextExtension(conformance_classes=[FreeTextConformanceClasses.COLLECTIONS]),
+]
+
+# Initialize collection search with its extensions
+collection_search_ext = CollectionSearchExtension.from_extensions(
+    collection_search_extensions
+)
+collections_get_request_model = collection_search_ext.GET
+
+extensions.append(collection_search_ext)
+
 database_logic.extensions = [type(ext).__name__ for ext in extensions]
 
 post_request_model = create_post_request_model(search_extensions)
diff --git a/stac_fastapi/opensearch/stac_fastapi/opensearch/app.py b/stac_fastapi/opensearch/stac_fastapi/opensearch/app.py
index 7ded95c9..15d21943 100644
--- a/stac_fastapi/opensearch/stac_fastapi/opensearch/app.py
+++ b/stac_fastapi/opensearch/stac_fastapi/opensearch/app.py
@@ -31,6 +31,7 @@
 from stac_fastapi.extensions.core import (
     AggregationExtension,
     CollectionSearchExtension,
+    CollectionSearchFilterExtension,
     FilterExtension,
     FreeTextExtension,
     SortExtension,
@@ -39,6 +40,7 @@
 )
 from stac_fastapi.extensions.core.fields import FieldsConformanceClasses
 from stac_fastapi.extensions.core.filter import FilterConformanceClasses
+from stac_fastapi.extensions.core.free_text import FreeTextConformanceClasses
 from stac_fastapi.extensions.core.query import QueryConformanceClasses
 from stac_fastapi.extensions.core.sort import SortConformanceClasses
 from stac_fastapi.extensions.third_party import BulkTransactionExtension
@@ -71,7 +73,6 @@
 
 # Adding collection search extension for compatibility with stac-auth-proxy
 # (https://github.com/developmentseed/stac-auth-proxy)
-# The extension is not fully implemented yet but is required for collection filtering support
 collection_search_extension = CollectionSearchExtension()
 collection_search_extension.conformance_classes.append(
     "https://api.stacspec.org/v1.0.0-rc.1/collection-search#filter"
@@ -85,6 +86,7 @@
 aggregation_extension.POST = EsAggregationExtensionPostRequest
 aggregation_extension.GET = EsAggregationExtensionGetRequest
 
+# Base search extensions (without CollectionSearchExtension to avoid duplicates)
 fields_extension = FieldsExtension()
 fields_extension.conformance_classes.append(FieldsConformanceClasses.ITEMS)
 
@@ -98,7 +100,6 @@
     collection_search_extension,
 ]
 
-
 if TRANSACTIONS_EXTENSIONS:
     search_extensions.insert(
         0,
@@ -120,8 +121,29 @@
         ),
     )
 
+# Initialize extensions with just the search and aggregation extensions
+# Initialize with base extensions
 extensions = [aggregation_extension] + search_extensions
 
+# Create collection search extensions
+collection_search_extensions = [
+    QueryExtension(conformance_classes=[QueryConformanceClasses.COLLECTIONS]),
+    SortExtension(conformance_classes=[SortConformanceClasses.COLLECTIONS]),
+    FieldsExtension(conformance_classes=[FieldsConformanceClasses.COLLECTIONS]),
+    CollectionSearchFilterExtension(
+        conformance_classes=[FilterConformanceClasses.COLLECTIONS]
+    ),
+    FreeTextExtension(conformance_classes=[FreeTextConformanceClasses.COLLECTIONS]),
+]
+
+# Initialize collection search with its extensions
+collection_search_ext = CollectionSearchExtension.from_extensions(
+    collection_search_extensions
+)
+collections_get_request_model = collection_search_ext.GET
+
+extensions.append(collection_search_ext)
+
 database_logic.extensions = [type(ext).__name__ for ext in extensions]
 
 post_request_model = create_post_request_model(search_extensions)
diff --git a/stac_fastapi/sfeos_helpers/stac_fastapi/sfeos_helpers/mappings.py b/stac_fastapi/sfeos_helpers/stac_fastapi/sfeos_helpers/mappings.py
index 17cdd1ea..a90a9c33 100644
--- a/stac_fastapi/sfeos_helpers/stac_fastapi/sfeos_helpers/mappings.py
+++ b/stac_fastapi/sfeos_helpers/stac_fastapi/sfeos_helpers/mappings.py
@@ -160,8 +160,17 @@ class Geometry(Protocol):  # noqa
     "dynamic_templates": ES_MAPPINGS_DYNAMIC_TEMPLATES,
     "properties": {
         "id": {"type": "keyword"},
-        "extent.spatial.bbox": {"type": "long"},
-        "extent.temporal.interval": {"type": "date"},
+        "bbox_shape": {"type": "geo_shape"},  # Only this is used for spatial queries
+        "extent": {
+            "properties": {"temporal": {"properties": {"interval": {"type": "date"}}}}
+        },
+        "properties": {
+            "properties": {
+                "datetime": {"type": "date"},
+                "start_datetime": {"type": "date"},
+                "end_datetime": {"type": "date"},
+            }
+        },
         "providers": {"type": "object", "enabled": False},
         "links": {"type": "object", "enabled": False},
         "item_assets": {"type": "object", "enabled": get_bool_env("STAC_INDEX_ASSETS")},