diff --git a/app/assets/javascripts/editor/schema/ci.json b/app/assets/javascripts/editor/schema/ci.json
index 8e307bc1f19a4ce0c7a636628394595e16b76bee..3a1188d7aabc373c5e8186309f1c2c8fdae8cfc1 100644
--- a/app/assets/javascripts/editor/schema/ci.json
+++ b/app/assets/javascripts/editor/schema/ci.json
@@ -830,7 +830,8 @@
                   {
                     "type": "string",
                     "enum": [
-                      "never"
+                      "never",
+                      "always"
                     ]
                   },
                   {
diff --git a/doc/ci/yaml/includes.md b/doc/ci/yaml/includes.md
index 5c818a81ff8a08d1dbedd22868acb2bdb70f58bd..69595b62de2107d1321084933e9725d21970a0a5 100644
--- a/doc/ci/yaml/includes.md
+++ b/doc/ci/yaml/includes.md
@@ -418,7 +418,7 @@ these keywords:
 
 ### `include` with `rules:if`
 
-> Support for `when: never` [introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/348146) in GitLab 16.1.
+> Support for `when: never` and `when:always` [introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/348146) in GitLab 16.1 [with a flag](../../administration/feature_flags.md) named `ci_support_include_rules_when_never`. Disabled by default.
 
 Use [`rules:if`](index.md#rulesif) to conditionally include other configuration files
 based on the status of CI/CD variables. For example:
@@ -429,6 +429,10 @@ include:
     rules:
       - if: $DONT_INCLUDE_BUILDS == "true"
         when: never
+  - local: builds.yml
+    rules:
+      - if: $ALWAYS_INCLUDE_BUILDS == "true"
+        when: always
   - local: builds.yml
     rules:
       - if: $INCLUDE_BUILDS == "true"
@@ -443,7 +447,7 @@ test:
 
 ### `include` with `rules:exists`
 
-> Support for `when: never` [introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/348146) in GitLab 16.1.
+> Support for `when: never` and `when:always` [introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/348146) in GitLab 16.1 [with a flag](../../administration/feature_flags.md) named `ci_support_include_rules_when_never`. Disabled by default.
 
 Use [`rules:exists`](index.md#rulesexists) to conditionally include other configuration files
 based on the existence of files. For example:
@@ -455,6 +459,11 @@ include:
       - exists:
           - exception-file.md
         when: never
+  - local: builds.yml
+    rules:
+      - exists:
+          - important-file.md
+        when: always
   - local: builds.yml
     rules:
       - exists:
diff --git a/lib/gitlab/ci/config/entry/include/rules/rule.rb b/lib/gitlab/ci/config/entry/include/rules/rule.rb
index 60ce43a1546e1996ebfeb630f9d6d8c820fbccd9..9cdbd8cd037dcd31a429f83d64f915dc389a079f 100644
--- a/lib/gitlab/ci/config/entry/include/rules/rule.rb
+++ b/lib/gitlab/ci/config/entry/include/rules/rule.rb
@@ -10,7 +10,7 @@ class Rules::Rule < ::Gitlab::Config::Entry::Node
             include ::Gitlab::Config::Entry::Attributable
 
             ALLOWED_KEYS = %i[if exists when].freeze
-            ALLOWED_WHEN = %w[never].freeze
+            ALLOWED_WHEN = %w[never always].freeze
 
             attributes :if, :exists, :when
 
diff --git a/lib/gitlab/ci/config/external/rules.rb b/lib/gitlab/ci/config/external/rules.rb
index 8aaa14b3d7bd173de00f3cf83bf893e8c28631bf..134306332e6c9b8cceef2f0565a90156aefb4b41 100644
--- a/lib/gitlab/ci/config/external/rules.rb
+++ b/lib/gitlab/ci/config/external/rules.rb
@@ -19,7 +19,7 @@ def initialize(rule_hashes)
           def evaluate(context)
             if Feature.enabled?(:ci_support_include_rules_when_never, context.project)
               if @rule_list.nil?
-                Result.new(nil)
+                Result.new('always')
               elsif matched_rule = match_rule(context)
                 Result.new(matched_rule.attributes[:when])
               else
diff --git a/spec/frontend/editor/schema/ci/yaml_tests/positive_tests/include.yml b/spec/frontend/editor/schema/ci/yaml_tests/positive_tests/include.yml
index fffdda8e6d6b31f0b5da4b93d2ed36fa22b5fa62..909911debf15a4103b9738af7f2a8641b01bbee1 100644
--- a/spec/frontend/editor/schema/ci/yaml_tests/positive_tests/include.yml
+++ b/spec/frontend/editor/schema/ci/yaml_tests/positive_tests/include.yml
@@ -5,8 +5,34 @@ stages:
 include:
   - local: builds.yml
     rules:
-      - if: '$INCLUDE_BUILDS == "false"'
+      - if: $DONT_INCLUDE_BUILDS == "true"
         when: never
+  - local: builds.yml
+    rules:
+      - if: $INCLUDE_BUILDS == "true"
+        when: always
+  - local: deploys.yml
+    rules:
+      - if: $CI_COMMIT_BRANCH == "main"
+  - local: builds.yml
+    rules:
+      - exists:
+          - exception-file.md
+        when: never
+  - local: builds.yml
+    rules:
+      - exists:
+          - file.md
+        when: always
+  - local: builds.yml
+    rules:
+      - exists:
+          - file.md
+        when: null
+  - local: deploys.yml
+    rules:
+      - exists:
+          - file.md
 
 # valid trigger:include
 trigger:include accepts project and file properties:
diff --git a/spec/lib/gitlab/ci/config/external/rules_spec.rb b/spec/lib/gitlab/ci/config/external/rules_spec.rb
index 3cb9dedbefe6d37ac3f3a3c51cc1b8ef34367be2..1ba5caa1d4bcdc2610059b300fd8e36fd743e17d 100644
--- a/spec/lib/gitlab/ci/config/external/rules_spec.rb
+++ b/spec/lib/gitlab/ci/config/external/rules_spec.rb
@@ -80,6 +80,20 @@
         end
       end
 
+      context 'with when: always' do
+        let(:rule_hashes) { [{ if: '$MY_VAR == "hello"', when: 'always' }] }
+
+        it_behaves_like 'when there is a rule with if'
+
+        context 'when FF `ci_support_include_rules_when_never` is disabled' do
+          before do
+            stub_feature_flags(ci_support_include_rules_when_never: false)
+          end
+
+          it_behaves_like 'when there is a rule with if'
+        end
+      end
+
       context 'with when: <invalid string>' do
         let(:rule_hashes) { [{ if: '$MY_VAR == "hello"', when: 'on_success' }] }
 
@@ -111,6 +125,20 @@
         end
       end
 
+      context 'with when: always' do
+        let(:rule_hashes) { [{ exists: 'Dockerfile', when: 'always' }] }
+
+        it_behaves_like 'when there is a rule with exists'
+
+        context 'when FF `ci_support_include_rules_when_never` is disabled' do
+          before do
+            stub_feature_flags(ci_support_include_rules_when_never: false)
+          end
+
+          it_behaves_like 'when there is a rule with exists'
+        end
+      end
+
       context 'with when: <invalid string>' do
         let(:rule_hashes) { [{ exists: 'Dockerfile', when: 'on_success' }] }