diff --git a/etc/openstack_deploy/user_variables.yml b/etc/openstack_deploy/user_variables.yml
index 6795014e07..fb7727496f 100644
--- a/etc/openstack_deploy/user_variables.yml
+++ b/etc/openstack_deploy/user_variables.yml
@@ -22,11 +22,14 @@
 debug: false
 
 ## Common Glance Overrides
-# Set glance_default_store to "swift" if using Cloud Files or swift backend
+# Set glance_default_store to "swift" if using Cloud Files backend
 # or "rbd" if using ceph backend; the latter will trigger ceph to get
 # installed on glance. If using a file store, a shared file store is
 # recommended. See the OpenStack-Ansible install guide and the OpenStack
 # documentation for more details.
+# Note that "swift" is automatically set as the default back-end if there
+# are any swift hosts in the environment. Use this setting to override
+# this automation if you wish for a different default back-end.
 # glance_default_store: file
 
 ## Ceph pool name for Glance to use
diff --git a/playbooks/inventory/group_vars/cinder_all.yml b/playbooks/inventory/group_vars/cinder_all.yml
index 4a30889852..57ceb0966f 100644
--- a/playbooks/inventory/group_vars/cinder_all.yml
+++ b/playbooks/inventory/group_vars/cinder_all.yml
@@ -13,6 +13,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# If there are Swift hosts in the environment, then use it as the default Glance store
+# This is specifically duplicated from glance_all for the cinder_glance_api_version
+# setting below.
+glance_default_store: "{{ ((groups['swift_all'] is defined) and (groups['swift_all'] | length > 0)) | ternary('swift', 'file') }}"
+
 # cinder_backend_lvm_inuse: True if current host has an lvm backend
 cinder_backend_lvm_inuse: '{{ (cinder_backends|default("")|to_json).find("cinder.volume.drivers.lvm.LVMVolumeDriver") != -1 }}'
 cinder_service_region: "{{ service_region }}"
diff --git a/playbooks/inventory/group_vars/glance_all.yml b/playbooks/inventory/group_vars/glance_all.yml
index ba2398569d..3de9f9cf4d 100644
--- a/playbooks/inventory/group_vars/glance_all.yml
+++ b/playbooks/inventory/group_vars/glance_all.yml
@@ -19,5 +19,8 @@ glance_service_in_ldap: "{{ service_ldap_backend_enabled }}"
 # If there are any Ceilometer hosts in the environment, then enable its usage
 glance_ceilometer_enabled: "{{ (groups['ceilometer_all'] is defined) and (groups['ceilometer_all'] | length > 0) }}"
 
+# If there are Swift hosts in the environment, then use it as the default Glance store
+glance_default_store: "{{ ((groups['swift_all'] is defined) and (groups['swift_all'] | length > 0)) | ternary('swift', 'file') }}"
+
 # Ensure that the package state matches the global setting
 glance_package_state: "{{ package_state }}"
diff --git a/releasenotes/notes/detect-glance-default-store-swift-b9c36f4a2fe05ec4.yaml b/releasenotes/notes/detect-glance-default-store-swift-b9c36f4a2fe05ec4.yaml
new file mode 100644
index 0000000000..073eea0752
--- /dev/null
+++ b/releasenotes/notes/detect-glance-default-store-swift-b9c36f4a2fe05ec4.yaml
@@ -0,0 +1,11 @@
+---
+features:
+  - If there are swift hosts in the environment, then the value for
+    ``glance_default_store`` will automatically be set to ``swift``.
+    This negates the need to set this variable in ``user_variables.yml``,
+    but the value may still be overridden at the deployer discretion.
+upgrade:
+  - If there are swift hosts in the environment, then the value for
+    ``glance_default_store`` will automatically be set to ``swift``.
+    This negates the need to set this variable in ``user_variables.yml``,
+    but the value may still be overridden at the deployer discretion.
diff --git a/tests/roles/bootstrap-host/templates/user_variables.aio.yml.j2 b/tests/roles/bootstrap-host/templates/user_variables.aio.yml.j2
index ee8a5a5733..cfeb3b04f7 100644
--- a/tests/roles/bootstrap-host/templates/user_variables.aio.yml.j2
+++ b/tests/roles/bootstrap-host/templates/user_variables.aio.yml.j2
@@ -16,9 +16,6 @@
 ## General options
 debug: True
 
-## Glance Options
-glance_default_store: swift
-
 ## Cinder settings
 cinder_service_backup_program_enabled: True