diff --git a/cms/djangoapps/contentstore/tests/test_import.py b/cms/djangoapps/contentstore/tests/test_import.py
index 1f6b393adca1..dbcef8e79ba7 100644
--- a/cms/djangoapps/contentstore/tests/test_import.py
+++ b/cms/djangoapps/contentstore/tests/test_import.py
@@ -13,6 +13,7 @@
 from django.conf import settings
 from django.test.client import Client
 from django.test.utils import override_settings
+from django.core.files.storage import storages
 
 from xmodule.contentstore.django import contentstore
 from xmodule.exceptions import NotFoundError
@@ -281,19 +282,24 @@ def test_video_components_present_while_import(self):
 
     @override_settings(
         COURSE_IMPORT_EXPORT_STORAGE="cms.djangoapps.contentstore.storage.ImportExportS3Storage",
-        DEFAULT_FILE_STORAGE="django.core.files.storage.FileSystemStorage"
+        STORAGES={
+            'default': {
+                'BACKEND': "django.core.files.storage.FileSystemStorage"
+            }
+        }
     )
-    def test_resolve_default_storage(self):
+    def test_default_storage(self):
         """ Ensure the default storage is invoked, even if course export storage is configured """
-        storage = resolve_storage_backend(
-            storage_key="default",
-            legacy_setting_key="DEFAULT_FILE_STORAGE"
-        )
+        storage = storages["default"]
         self.assertEqual(storage.__class__.__name__, "FileSystemStorage")
 
     @override_settings(
         COURSE_IMPORT_EXPORT_STORAGE="cms.djangoapps.contentstore.storage.ImportExportS3Storage",
-        DEFAULT_FILE_STORAGE="django.core.files.storage.FileSystemStorage",
+        STORAGES={
+            'default': {
+                'BACKEND': "django.core.files.storage.FileSystemStorage"
+            }
+        },
         COURSE_IMPORT_EXPORT_BUCKET="bucket_name_test"
     )
     def test_resolve_happy_path_storage(self):
diff --git a/cms/djangoapps/export_course_metadata/test_signals.py b/cms/djangoapps/export_course_metadata/test_signals.py
index de3aaf6df232..876dcb224c18 100644
--- a/cms/djangoapps/export_course_metadata/test_signals.py
+++ b/cms/djangoapps/export_course_metadata/test_signals.py
@@ -12,6 +12,7 @@
 from xmodule.modulestore.tests.factories import CourseFactory, BlockFactory
 from common.djangoapps.util.storage import resolve_storage_backend
 from storages.backends.s3boto3 import S3Boto3Storage
+from django.core.files.storage import storages
 
 from .signals import export_course_metadata
 from .toggles import EXPORT_COURSE_METADATA_FLAG
@@ -60,16 +61,24 @@ def test_happy_path(self, patched_content, patched_storage):
 
     @override_settings(
         COURSE_METADATA_EXPORT_STORAGE="cms.djangoapps.export_course_metadata.storage.CourseMetadataExportS3Storage",
-        DEFAULT_FILE_STORAGE="django.core.files.storage.FileSystemStorage"
+        STORAGES={
+            'default': {
+                'BACKEND': "django.core.files.storage.FileSystemStorage"
+            }
+        }
     )
     def test_resolve_default_storage(self):
         """ Ensure the default storage is invoked, even if course export storage is configured """
-        storage = resolve_storage_backend(storage_key="default", legacy_setting_key="default")
+        storage = storages["default"]
         self.assertEqual(storage.__class__.__name__, "FileSystemStorage")
 
     @override_settings(
         COURSE_METADATA_EXPORT_STORAGE="cms.djangoapps.export_course_metadata.storage.CourseMetadataExportS3Storage",
-        DEFAULT_FILE_STORAGE="django.core.files.storage.FileSystemStorage",
+        STORAGES={
+            "default": {
+                "BACKEND": "django.core.files.storage.FileSystemStorage"
+            }
+        },
         COURSE_METADATA_EXPORT_BUCKET="bucket_name_test"
     )
     def test_resolve_happy_path_storage(self):
diff --git a/cms/envs/common.py b/cms/envs/common.py
index ee0e61c0d0f1..13811d2a1321 100644
--- a/cms/envs/common.py
+++ b/cms/envs/common.py
@@ -1157,7 +1157,6 @@
     'YUI_BINARY': 'yui-compressor',
 }
 
-STATICFILES_STORAGE = 'openedx.core.storage.ProductionStorage'
 STATICFILES_STORAGE_KWARGS = {}
 
 # List of finder classes that know how to find static files in various locations.
@@ -2386,7 +2385,15 @@
 BULK_EMAIL_LOG_SENT_EMAILS = False
 
 ############### Settings for django file storage ##################
-DEFAULT_FILE_STORAGE = 'django.core.files.storage.FileSystemStorage'
+STORAGES = {
+    'default': {
+        'BACKEND': 'django.core.files.storage.FileSystemStorage'
+    },
+    'staticfiles': {
+        'BACKEND': 'openedx.core.storage.ProductionStorage'
+    }
+}
+
 
 ###################### Grade Downloads ######################
 # These keys are used for all of our asynchronous downloadable files, including
diff --git a/cms/envs/devstack.py b/cms/envs/devstack.py
index 6ff0b0378960..bda53a366ca2 100644
--- a/cms/envs/devstack.py
+++ b/cms/envs/devstack.py
@@ -9,7 +9,7 @@
 from .production import *  # pylint: disable=wildcard-import, unused-wildcard-import
 
 # Don't use S3 in devstack, fall back to filesystem
-del DEFAULT_FILE_STORAGE
+STORAGES['default']['BACKEND'] = 'django.core.files.storage.FileSystemStorage'
 COURSE_IMPORT_EXPORT_STORAGE = 'django.core.files.storage.FileSystemStorage'
 USER_TASKS_ARTIFACT_STORAGE = COURSE_IMPORT_EXPORT_STORAGE
 
@@ -56,7 +56,7 @@
 
 # Skip packaging and optimization in development
 PIPELINE['PIPELINE_ENABLED'] = False
-STATICFILES_STORAGE = 'openedx.core.storage.DevelopmentStorage'
+STORAGES['staticfiles']['BACKEND'] = 'openedx.core.storage.DevelopmentStorage'
 
 # Revert to the default set of finders as we don't want the production pipeline
 STATICFILES_FINDERS = [
diff --git a/cms/envs/mock.yml b/cms/envs/mock.yml
index d5f48151f8ab..b28ee6028073 100644
--- a/cms/envs/mock.yml
+++ b/cms/envs/mock.yml
@@ -291,7 +291,11 @@ DATABASES:
     USER: user
 DATA_DIR: /edx/var/edxapp
 DEFAULT_FEEDBACK_EMAIL: feedback@example.com
-DEFAULT_FILE_STORAGE: storages.backends.s3boto3.S3Boto3Storage
+STORAGES:
+    default:
+      BACKEND: storages.backends.s3boto3.S3Boto3Storage
+    staticfiles:
+      BACKEND: openedx.core.storage.ProductionStorage
 DEFAULT_FROM_EMAIL: no-reply@registration.localhost
 DEFAULT_HASHING_ALGORITHM: sha256
 DEFAULT_JWT_ISSUER:
diff --git a/cms/envs/production.py b/cms/envs/production.py
index 7bc4677d80c0..346a60da66f9 100644
--- a/cms/envs/production.py
+++ b/cms/envs/production.py
@@ -82,10 +82,11 @@ def get_env_setting(setting):
             'MKTG_URL_LINK_MAP',
             'REST_FRAMEWORK',
             'EVENT_BUS_PRODUCER_CONFIG',
+            'DEFAULT_FILE_STORAGE',
+            'STATICFILES_STORAGE',
         ]
     })
 
-
 #######################################################################################################################
 #### LOAD THE EDX-PLATFORM GIT REVISION
 ####
@@ -150,11 +151,6 @@ def get_env_setting(setting):
 if 'staticfiles' in CACHES:
     CACHES['staticfiles']['KEY_PREFIX'] = EDX_PLATFORM_REVISION
 
-# In order to transition from local disk asset storage to S3 backed asset storage,
-# we need to run asset collection twice, once for local disk and once for S3.
-# Once we have migrated to service assets off S3, then we can convert this back to
-# managed by the yaml file contents
-STATICFILES_STORAGE = os.environ.get('STATICFILES_STORAGE', STATICFILES_STORAGE)
 
 MKTG_URL_LINK_MAP.update(_YAML_TOKENS.get('MKTG_URL_LINK_MAP', {}))
 
@@ -194,21 +190,38 @@ def get_env_setting(setting):
 # The number of seconds that a generated URL is valid for.
 AWS_QUERYSTRING_EXPIRE = 7 * 24 * 60 * 60  # 7 days
 
-# Change to S3Boto3 if we haven't specified another default storage AND we have specified AWS creds.
-if (not _YAML_TOKENS.get('DEFAULT_FILE_STORAGE')) and AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY:
-    DEFAULT_FILE_STORAGE = 'storages.backends.s3boto3.S3Boto3Storage'
+_yaml_storages = _YAML_TOKENS.get('STORAGES', {})
+
+_storages_default_backend_is_missing = not _yaml_storages.get('default', {}).get('BACKEND')
+
+# For backward compatibility, if YAML provides legacy keys (DEFAULT_FILE_STORAGE, STATICFILES_STORAGE)
+# and STORAGES doesn’t explicitly define the corresponding backend, migrate the legacy value into STORAGES.
+# If YAML doesn't provide lagacy keys, no backend is defined in STORAGES['default'] and AWS creds are present,
+# fall back to S3Boto3Storage.
+#
+# This ensures YAML-provided values take precedence over defaults from common.py,
+# without overwriting user-defined STORAGES and AWS creds are treated only as a fallback.
+if _storages_default_backend_is_missing:
+    if 'DEFAULT_FILE_STORAGE' in _YAML_TOKENS:
+        STORAGES['default']['BACKEND'] = _YAML_TOKENS['DEFAULT_FILE_STORAGE']
+    elif AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY:
+        STORAGES['default']['BACKEND'] = 'storages.backends.s3boto3.S3Boto3Storage'
+
+# Apply legacy STATICFILES_STORAGE if no backend is defined for "staticfiles"
+if 'STATICFILES_STORAGE' in _YAML_TOKENS and not _yaml_storages.get('staticfiles', {}).get('BACKEND'):
+    STORAGES['staticfiles']['BACKEND'] = _YAML_TOKENS['STATICFILES_STORAGE']
 
 if COURSE_IMPORT_EXPORT_BUCKET:
     COURSE_IMPORT_EXPORT_STORAGE = 'cms.djangoapps.contentstore.storage.ImportExportS3Storage'
 else:
-    COURSE_IMPORT_EXPORT_STORAGE = DEFAULT_FILE_STORAGE
+    COURSE_IMPORT_EXPORT_STORAGE = STORAGES['default']['BACKEND']
 
 USER_TASKS_ARTIFACT_STORAGE = COURSE_IMPORT_EXPORT_STORAGE
 
 if COURSE_METADATA_EXPORT_BUCKET:
     COURSE_METADATA_EXPORT_STORAGE = 'cms.djangoapps.export_course_metadata.storage.CourseMetadataExportS3Storage'
 else:
-    COURSE_METADATA_EXPORT_STORAGE = DEFAULT_FILE_STORAGE
+    COURSE_METADATA_EXPORT_STORAGE = STORAGES['default']['BACKEND']
 
 # The normal database user does not have enough permissions to run migrations.
 # Migrations are run with separate credentials, given as DB_MIGRATION_*
diff --git a/cms/envs/test.py b/cms/envs/test.py
index deef2b8ff323..23131c699f91 100644
--- a/cms/envs/test.py
+++ b/cms/envs/test.py
@@ -29,7 +29,6 @@
 from lms.envs.test import (  # pylint: disable=wrong-import-order, disable=unused-import
     ACCOUNT_MICROFRONTEND_URL,
     COMPREHENSIVE_THEME_DIRS,  # unimport:skip
-    DEFAULT_FILE_STORAGE,
     ECOMMERCE_API_URL,
     ENABLE_COMPREHENSIVE_THEMING,
     JWT_AUTH,
@@ -91,7 +90,7 @@
 # If we don't add these settings, then Django templates that can't
 # find pipelined assets will raise a ValueError.
 # http://stackoverflow.com/questions/12816941/unit-testing-with-django-pipeline
-STATICFILES_STORAGE = "pipeline.storage.NonPackagingPipelineStorage"
+STORAGES['staticfiles']['BACKEND'] = "pipeline.storage.NonPackagingPipelineStorage"
 STATIC_URL = "/static/"
 
 # Update module store settings per defaults for tests
diff --git a/common/djangoapps/util/file.py b/common/djangoapps/util/file.py
index b2892e6f42c9..9397cdff939d 100644
--- a/common/djangoapps/util/file.py
+++ b/common/djangoapps/util/file.py
@@ -78,7 +78,7 @@ def store_uploaded_file(
         file_storage = DefaultStorage()
         # If a file already exists with the supplied name, file_storage will make the filename unique.
         stored_file_name = file_storage.save(stored_file_name, uploaded_file)
-        if is_private and settings.DEFAULT_FILE_STORAGE == 'storages.backends.s3boto3.S3Boto3Storage':
+        if is_private and settings.STORAGES['default']['BACKEND'] == 'storages.backends.s3boto3.S3Boto3Storage':
             S3Boto3Storage().connection.meta.client.put_object_acl(
                 ACL='private',
                 Bucket=settings.AWS_STORAGE_BUCKET_NAME,
diff --git a/common/djangoapps/util/storage.py b/common/djangoapps/util/storage.py
index 37f908cd2799..b818acf90017 100644
--- a/common/djangoapps/util/storage.py
+++ b/common/djangoapps/util/storage.py
@@ -38,9 +38,7 @@ def resolve_storage_backend(
 
     storage_path = getattr(settings, legacy_setting_key, None)
     storages_config = getattr(settings, 'STORAGES', {})
-
-    if options is None:
-        options = {}
+    options = options or {}
 
     if storage_key in storages_config:
         # Use case 1: STORAGES is defined
@@ -70,5 +68,5 @@ def resolve_storage_backend(
                 break
             storage_path = storage_path.get(deep_setting_key)
 
-    StorageClass = import_string(storage_path or settings.DEFAULT_FILE_STORAGE)
+    StorageClass = import_string(storage_path or storages_config["default"]["BACKEND"])
     return StorageClass(**options)
diff --git a/common/djangoapps/util/tests/test_resolve_storage_backend.py b/common/djangoapps/util/tests/test_resolve_storage_backend.py
index d892243c14cb..cf0e0cbd0e94 100644
--- a/common/djangoapps/util/tests/test_resolve_storage_backend.py
+++ b/common/djangoapps/util/tests/test_resolve_storage_backend.py
@@ -4,6 +4,7 @@
 
 from django.test import TestCase
 from django.test.utils import override_settings
+from unittest.mock import patch, MagicMock
 
 from common.djangoapps.util.storage import resolve_storage_backend
 
@@ -20,6 +21,7 @@ class ResolveStorageTest(TestCase):
         BLOCK_STRUCTURES_SETTINGS="cms.djangoapps.contentstore.storage.ImportExportS3Storage"
     )
     def test_legacy_settings(self):
+        """Test legacy string-based storage settings."""
         storage = resolve_storage_backend(
             storage_key="block_structures_settings",
             legacy_setting_key="BLOCK_STRUCTURES_SETTINGS",
@@ -33,6 +35,7 @@ def test_legacy_settings(self):
         }
     )
     def test_nested_legacy_settings(self):
+        """Test legacy nested dictionary."""
         storage = resolve_storage_backend(
             storage_key="block_structures_settings",
             legacy_setting_key="BLOCK_STRUCTURES_SETTINGS",
@@ -47,6 +50,7 @@ def test_nested_legacy_settings(self):
         }
     )
     def test_nested_legacy_settings_failed(self):
+        """Test legacy nested dictionary settings with missing key falls back to default."""
         storage = resolve_storage_backend(
             storage_key="block_structures_settings",
             legacy_setting_key="BLOCK_STRUCTURES_SETTINGS",
@@ -54,3 +58,75 @@ def test_nested_legacy_settings_failed(self):
             options={}
         )
         assert storage.__class__.__name__ == DEFAULT_STORAGE_CLASS_NAME
+
+    @override_settings(
+        STORAGES={
+            "default": {
+                "BACKEND": "django.core.files.storage.FileSystemStorage",
+                "OPTIONS": {}
+            }
+        },
+        LEGACY_SETTING="cms.djangoapps.contentstore.storage.ImportExportS3Storage"
+    )
+    def test_missing_storage_key_fallback_to_legacy(self):
+        """Test fallback to legacy settings when storage key not found in STORAGES."""
+        storage = resolve_storage_backend(
+            storage_key="nonexistent_storage",
+            legacy_setting_key="LEGACY_SETTING",
+            options={}
+        )
+        assert storage.__class__.__name__ == "ImportExportS3Storage"
+
+    def test_no_storages_no_legacy_setting(self):
+        """Test fallback to default storage when neither STORAGES nor legacy setting exists."""
+        storage = resolve_storage_backend(
+            storage_key="nonexistent_storage",
+            legacy_setting_key="NONEXISTENT_LEGACY_SETTING",
+            options={}
+        )
+        assert storage.__class__.__name__ == DEFAULT_STORAGE_CLASS_NAME
+
+    @override_settings(
+        STORAGES={
+            "default": {
+                "BACKEND": "cms.djangoapps.contentstore.storage.ImportExportS3Storage",
+                "OPTIONS": {}
+            }
+        }
+    )
+    def test_fallback_to_custom_default_backend(self):
+        """Test fallback uses custom default backend from STORAGES config."""
+        storage = resolve_storage_backend(
+            storage_key="nonexistent_storage",
+            legacy_setting_key="NONEXISTENT_LEGACY_SETTING",
+            options={}
+        )
+        assert storage.__class__.__name__ == "ImportExportS3Storage"
+
+    @override_settings(
+        STORAGES={
+            "default": {
+                "BACKEND": "django.core.files.storage.FileSystemStorage",
+                "OPTIONS": {}
+            },
+            "custom_storage_key": {
+                "BACKEND": "cms.djangoapps.contentstore.storage.ImportExportS3Storage",
+                "OPTIONS": {}
+            }
+        }
+    )
+    @patch('common.djangoapps.util.storage.storages')
+    def test_modern_storages_config(self, mock_storages):
+        """Test modern Django STORAGES configuration that takes precedence."""
+        mock_storage_instance = MagicMock()
+        mock_storage_instance.__class__.__name__ = "ImportExportS3Storage"
+        mock_storages.__getitem__.return_value = mock_storage_instance
+
+        storage = resolve_storage_backend(
+            storage_key="custom_storage_key",
+            legacy_setting_key="SOME_LEGACY_SETTING",
+            options={}
+        )
+
+        mock_storages.__getitem__.assert_called_once_with("custom_storage_key")
+        assert storage.__class__.__name__ == "ImportExportS3Storage"
diff --git a/lms/djangoapps/instructor_task/models.py b/lms/djangoapps/instructor_task/models.py
index 913e4775a946..fb5eef52a327 100644
--- a/lms/djangoapps/instructor_task/models.py
+++ b/lms/djangoapps/instructor_task/models.py
@@ -272,12 +272,12 @@ def __init__(self, storage_class=None, storage_kwargs=None):
     @classmethod
     def from_config(cls, config_name):
         """
-        By default, the default file storage specified by the `DEFAULT_FILE_STORAGE`
+        By default, the default file storage specified by the `STORAGES['default']`
         setting will be used. To configure the storage used, add a dict in
         settings with the following fields::
 
             STORAGE_CLASS : The import path of the storage class to use. If
-                            not set, the DEFAULT_FILE_STORAGE setting will be used.
+                            not set, the STORAGES['default']['BACKEND'] setting will be used.
             STORAGE_KWARGS : An optional dict of kwargs to pass to the storage
                              constructor. This can be used to specify a
                              different S3 bucket or root path, for example.
diff --git a/lms/envs/common.py b/lms/envs/common.py
index 5b33f9bcb160..2075f3e70fac 100644
--- a/lms/envs/common.py
+++ b/lms/envs/common.py
@@ -2182,7 +2182,6 @@
     'UGLIFYJS_BINARY': 'node_modules/.bin/uglifyjs',
 }
 
-STATICFILES_STORAGE = 'openedx.core.storage.ProductionStorage'
 STATICFILES_STORAGE_KWARGS = {}
 
 # List of finder classes that know how to find static files in various locations.
@@ -4609,7 +4608,14 @@
 }
 
 ############### Settings for django file storage ##################
-DEFAULT_FILE_STORAGE = 'django.core.files.storage.FileSystemStorage'
+STORAGES = {
+    'default': {
+        'BACKEND': 'django.core.files.storage.FileSystemStorage'
+    },
+    'staticfiles': {
+        'BACKEND': 'openedx.core.storage.ProductionStorage'
+    }
+}
 
 ### Proctoring configuration (redirct URLs and keys shared between systems) ####
 PROCTORING_BACKENDS = {
diff --git a/lms/envs/devstack.py b/lms/envs/devstack.py
index 8f25169cbd60..a2ee3ea9d8ee 100644
--- a/lms/envs/devstack.py
+++ b/lms/envs/devstack.py
@@ -17,7 +17,7 @@
 from .production import *  # pylint: disable=wildcard-import, unused-wildcard-import
 
 # Don't use S3 in devstack, fall back to filesystem
-del DEFAULT_FILE_STORAGE
+STORAGES['default']['BACKEND'] = 'django.core.files.storage.FileSystemStorage'
 ORA2_FILEUPLOAD_BACKEND = 'django'
 
 
@@ -123,7 +123,7 @@ def should_show_debug_toolbar(request):  # lint-amnesty, pylint: disable=missing
 ########################### PIPELINE #################################
 
 PIPELINE['PIPELINE_ENABLED'] = False
-STATICFILES_STORAGE = 'openedx.core.storage.DevelopmentStorage'
+STORAGES['staticfiles']['BACKEND'] = 'openedx.core.storage.DevelopmentStorage'
 
 # Revert to the default set of finders as we don't want the production pipeline
 STATICFILES_FINDERS = [
diff --git a/lms/envs/mock.yml b/lms/envs/mock.yml
index 565ad043efbe..4d173abcd78b 100644
--- a/lms/envs/mock.yml
+++ b/lms/envs/mock.yml
@@ -376,7 +376,11 @@ DATABASES:
 DATA_DIR: /edx/var/edxapp
 DEFAULT_COURSE_VISIBILITY_IN_CATALOG: both
 DEFAULT_FEEDBACK_EMAIL: feedback@example.com
-DEFAULT_FILE_STORAGE: storages.backends.s3boto3.S3Boto3Storage
+STORAGES:
+    default:
+      BACKEND: storages.backends.s3boto3.S3Boto3Storage
+    staticfiles:
+      BACKEND: openedx.core.storage.ProductionStorage
 DEFAULT_FROM_EMAIL: sandbox-notifications@example.com
 DEFAULT_HASHING_ALGORITHM: sha256
 DEFAULT_JWT_ISSUER:
diff --git a/lms/envs/production.py b/lms/envs/production.py
index 6b91bfee36b2..584ebf726e0b 100644
--- a/lms/envs/production.py
+++ b/lms/envs/production.py
@@ -77,10 +77,11 @@ def get_env_setting(setting):
             'MKTG_URL_LINK_MAP',
             'REST_FRAMEWORK',
             'EVENT_BUS_PRODUCER_CONFIG',
+            'DEFAULT_FILE_STORAGE',
+            'STATICFILES_STORAGE',
         ]
     })
 
-
 #######################################################################################################################
 #### LOAD THE EDX-PLATFORM GIT REVISION
 ####
@@ -218,9 +219,26 @@ def get_env_setting(setting):
 AWS_DEFAULT_ACL = 'public-read'
 AWS_BUCKET_ACL = AWS_DEFAULT_ACL
 
-# Change to S3Boto3 if we haven't specified another default storage AND we have specified AWS creds.
-if (not _YAML_TOKENS.get('DEFAULT_FILE_STORAGE')) and AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY:
-    DEFAULT_FILE_STORAGE = 'storages.backends.s3boto3.S3Boto3Storage'
+_yaml_storages = _YAML_TOKENS.get('STORAGES', {})
+
+_storages_default_backend_is_missing = not _yaml_storages.get('default', {}).get('BACKEND')
+
+# For backward compatibility, if YAML provides legacy keys (DEFAULT_FILE_STORAGE, STATICFILES_STORAGE)
+# and STORAGES doesn’t explicitly define the corresponding backend, migrate the legacy value into STORAGES.
+# If YAML doesn't provide lagacy keys, no backend is defined in STORAGES['default'] and AWS creds are present,
+# fall back to S3Boto3Storage.
+#
+# This ensures YAML-provided values take precedence over defaults from common.py,
+# without overwriting user-defined STORAGES and AWS creds are treated only as a fallback.
+if _storages_default_backend_is_missing:
+    if 'DEFAULT_FILE_STORAGE' in _YAML_TOKENS:
+        STORAGES['default']['BACKEND'] = _YAML_TOKENS['DEFAULT_FILE_STORAGE']
+    elif AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY:
+        STORAGES['default']['BACKEND'] = 'storages.backends.s3boto3.S3Boto3Storage'
+
+# Apply legacy STATICFILES_STORAGE if no backend is defined for "staticfiles"
+if 'STATICFILES_STORAGE' in _YAML_TOKENS and not _yaml_storages.get('staticfiles', {}).get('BACKEND'):
+    STORAGES['staticfiles']['BACKEND'] = _YAML_TOKENS['STATICFILES_STORAGE']
 
 # The normal database user does not have enough permissions to run migrations.
 # Migrations are run with separate credentials, given as DB_MIGRATION_*
diff --git a/lms/envs/test.py b/lms/envs/test.py
index 2fb61b5dc5a9..c78604c0c1fb 100644
--- a/lms/envs/test.py
+++ b/lms/envs/test.py
@@ -151,7 +151,7 @@
 # If we don't add these settings, then Django templates that can't
 # find pipelined assets will raise a ValueError.
 # http://stackoverflow.com/questions/12816941/unit-testing-with-django-pipeline
-STATICFILES_STORAGE = 'pipeline.storage.NonPackagingPipelineStorage'
+STORAGES['staticfiles']['BACKEND'] = 'pipeline.storage.NonPackagingPipelineStorage'
 
 # Don't use compression during tests
 PIPELINE['JS_COMPRESSOR'] = None
@@ -298,7 +298,7 @@
 ])
 
 ############################ STATIC FILES #############################
-DEFAULT_FILE_STORAGE = 'django.core.files.storage.FileSystemStorage'
+STORAGES['default']['BACKEND'] = 'django.core.files.storage.FileSystemStorage'
 MEDIA_ROOT = TEST_ROOT / "uploads"
 MEDIA_URL = "/uploads/"
 STATICFILES_DIRS.append(("uploads", MEDIA_ROOT))
diff --git a/openedx/core/djangoapps/theming/tests/test_views.py b/openedx/core/djangoapps/theming/tests/test_views.py
index 5b5503702cd8..d4a990d11f54 100644
--- a/openedx/core/djangoapps/theming/tests/test_views.py
+++ b/openedx/core/djangoapps/theming/tests/test_views.py
@@ -100,7 +100,13 @@ def test_asset_no_theme(self):
         assert response.status_code == 302
         assert response.url == "/static/images/logo.png"
 
-    @override_settings(STATICFILES_STORAGE="openedx.core.storage.DevelopmentStorage")
+    @override_settings(
+        STORAGES={
+            'staticfiles': {
+                'BACKEND': 'openedx.core.storage.DevelopmentStorage'
+            }
+        }
+    )
     def test_asset_with_theme(self):
         """
         Fetch theme asset when a theme is set.
diff --git a/openedx/core/djangoapps/user_api/accounts/tests/test_views.py b/openedx/core/djangoapps/user_api/accounts/tests/test_views.py
index 466e1e278abd..497665489c37 100644
--- a/openedx/core/djangoapps/user_api/accounts/tests/test_views.py
+++ b/openedx/core/djangoapps/user_api/accounts/tests/test_views.py
@@ -1231,7 +1231,6 @@ def test_profile_backend_with_profile_image_settings(self):
     )
     def test_profile_backend_with_default_hardcoded_backend(self):
         """ In case of empty storages scenario uses the hardcoded backend."""
-        del settings.DEFAULT_FILE_STORAGE
         del settings.STORAGES
         storage = get_profile_image_storage()
         self.assertIsInstance(storage, FileSystemStorage)
diff --git a/openedx/core/storage.py b/openedx/core/storage.py
index 9e7e52d94c17..5dd0873d2724 100644
--- a/openedx/core/storage.py
+++ b/openedx/core/storage.py
@@ -54,7 +54,7 @@ class ProductionMixin(
     We use this version on production.
     """
     def __init__(self, *args, **kwargs):
-        kwargs.update(settings.STATICFILES_STORAGE_KWARGS.get(settings.STATICFILES_STORAGE, {}))
+        kwargs.update(settings.STATICFILES_STORAGE_KWARGS.get(settings.STORAGES['staticfiles']['BACKEND'], {}))
         super().__init__(*args, **kwargs)  # lint-amnesty, pylint: disable=super-with-arguments
 
 
@@ -112,5 +112,5 @@ class name is not given, an instance of the default storage is returned.
     the storage implementation makes http requests when instantiated, for
     example.
     """
-    storage_cls = import_string(storage_class or settings.DEFAULT_FILE_STORAGE)
+    storage_cls = import_string(storage_class or settings.STORAGES["default"]["BACKEND"])
     return storage_cls(**kwargs)
diff --git a/openedx/core/tests/test_storage.py b/openedx/core/tests/test_storage.py
new file mode 100644
index 000000000000..1a15786ba58e
--- /dev/null
+++ b/openedx/core/tests/test_storage.py
@@ -0,0 +1,54 @@
+"""
+Tests for the get_storage utility function.
+"""
+
+from django.test import TestCase, override_settings
+from django.core.files.storage import FileSystemStorage
+
+from openedx.core.storage import get_storage
+
+
+class TestGetStorage(TestCase):
+    """
+    Tests of the get_storage function
+    """
+
+    def setUp(self):
+        super().setUp()
+        get_storage.cache_clear()
+
+    def tearDown(self):
+        get_storage.cache_clear()
+
+    @override_settings(
+        STORAGES={
+            'default': {
+                'BACKEND': 'django.core.files.storage.FileSystemStorage'
+            }
+        }
+    )
+    def test_get_storage_returns_default_storage_when_no_class_specified(self):
+        """Test that get_storage returns the default storage when no storage_class is provided."""
+        storage = get_storage()
+        self.assertIsInstance(storage, FileSystemStorage)
+
+    def test_get_storage_returns_custom_storage_when_class_specified(self):
+        """Test that get_storage returns the specified storage class."""
+        storage_class = 'django.core.files.storage.FileSystemStorage'
+        storage = get_storage(storage_class=storage_class)
+        self.assertIsInstance(storage, FileSystemStorage)
+
+    def test_get_storage_caching_behavior(self):
+        """Test that get_storage caches instances with identical arguments."""
+        storage_class = 'django.core.files.storage.FileSystemStorage'
+        kwargs = {'location': '/test/path'}
+        # First Call
+        storage1 = get_storage(storage_class=storage_class, **kwargs)
+        # Second Call
+        storage2 = get_storage(storage_class=storage_class, **kwargs)
+        self.assertIs(storage1, storage2)
+
+    def test_get_storage_handles_invalid_storage_class(self):
+        """Test that get_storage raises appropriate error for invalid storage class."""
+        with self.assertRaises(ImportError):
+            get_storage(storage_class='nonexistent.storage.InvalidStorage')