diff --git a/CHANGELOG.md b/CHANGELOG.md
index 398e9904f07..65d598ed330 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -32,6 +32,7 @@
 * Add the method name to highlight area of `Layout/EmptyLineBetweenDefs` to help provide more context. ([@rrosenblum][])
 * [#7652](https://github.com/rubocop-hq/rubocop/pull/7652): Allow `pp` to allowed names of `Naming/MethodParameterName` cop in default config. ([@masarakki][])
 * [#7309](https://github.com/rubocop-hq/rubocop/pull/7309): Mark `Lint/UselessSetterCall` an "not safe" and improve documentation. ([@jonas054][])
+* [#7723](https://github.com/rubocop-hq/rubocop/pull/7723): Enable `Migration/DepartmentName` cop by default. ([@koic][])
 
 ## 0.79.0 (2020-01-06)
 
diff --git a/config/default.yml b/config/default.yml
index fa1b2bac08c..68a3f289f4d 100644
--- a/config/default.yml
+++ b/config/default.yml
@@ -1887,7 +1887,7 @@ Migration/DepartmentName:
   Description: >-
                  Check that cop names in rubocop:disable (etc) comments are
                  given with department name.
-  Enabled: false
+  Enabled: true
 
 #################### Naming ##############################
 
diff --git a/manual/cops_migration.md b/manual/cops_migration.md
index 6f154cbae5f..bb141d012cf 100644
--- a/manual/cops_migration.md
+++ b/manual/cops_migration.md
@@ -4,7 +4,7 @@
 
 Enabled by default | Safe | Supports autocorrection | VersionAdded | VersionChanged
 --- | --- | --- | --- | ---
-Disabled | Yes | Yes  | - | -
+Enabled | Yes | Yes  | - | -
 
 Check that cop names in rubocop:disable comments are given with
 department name.
diff --git a/spec/rubocop/cli/cli_auto_gen_config_spec.rb b/spec/rubocop/cli/cli_auto_gen_config_spec.rb
index 978db6f6c27..95a4aa82bb9 100644
--- a/spec/rubocop/cli/cli_auto_gen_config_spec.rb
+++ b/spec/rubocop/cli/cli_auto_gen_config_spec.rb
@@ -368,6 +368,12 @@ def f
                 '  Exclude:',
                 "    - 'example1.rb'",
                 '',
+                '# Offense count: 2',
+                '# Cop supports --auto-correct.',
+                'Migration/DepartmentName:',
+                '  Exclude:',
+                "    - 'example1.rb'",
+                '',
                 '# Offense count: 1',
                 '# Cop supports --auto-correct.',
                 '# Configuration parameters: EnforcedStyle.',
diff --git a/spec/rubocop/cli/cli_options_spec.rb b/spec/rubocop/cli/cli_options_spec.rb
index 499c52291d9..88be506c50e 100644
--- a/spec/rubocop/cli/cli_options_spec.rb
+++ b/spec/rubocop/cli/cli_options_spec.rb
@@ -464,10 +464,11 @@ class SomeCop < Cop
             1  Layout/SpaceAroundOperators
             1  Layout/Tab
             1  Layout/TrailingWhitespace
+            1  Migration/DepartmentName
             1  Style/FrozenStringLiteralComment
             1  Style/NumericPredicate
             --
-            6  Total
+            7  Total
 
           RESULT
       end
@@ -584,6 +585,7 @@ class SomeCop < Cop
       expect($stdout.string).to eq(<<~RESULT)
         #{file}:1:1: C: Style/FrozenStringLiteralComment: Missing frozen string literal comment.
         #{file}:1:8: W: Lint/RedundantCopDisableDirective: Unnecessary disabling of `Style/NumericLiterals`.
+        #{file}:1:26: C: Migration/DepartmentName: Department name is missing.
         #{file}:1:41: C: Layout/TrailingWhitespace: Trailing whitespace detected.
       RESULT
     end
@@ -595,6 +597,7 @@ class SomeCop < Cop
         expect($stdout.string).to eq(<<~RESULT)
           #{file}:1:1: C: Missing frozen string literal comment.
           #{file}:1:8: W: Unnecessary disabling of `Style/NumericLiterals`.
+          #{file}:1:26: C: Department name is missing.
           #{file}:1:41: C: Trailing whitespace detected.
         RESULT
       end
@@ -614,6 +617,7 @@ class SomeCop < Cop
         expect($stdout.string).to eq(<<~RESULT)
           #{file}:1:1: C: Style/FrozenStringLiteralComment: Missing frozen string literal comment.
           #{file}:1:8: W: Lint/RedundantCopDisableDirective: Unnecessary disabling of `Style/NumericLiterals`.
+          #{file}:1:26: C: Migration/DepartmentName: Department name is missing.
           #{file}:1:41: C: Layout/TrailingWhitespace: Trailing whitespace detected.
         RESULT
       end
@@ -624,6 +628,7 @@ class SomeCop < Cop
           expect($stdout.string).to eq(<<~RESULT)
             #{file}:1:1: C: Missing frozen string literal comment.
             #{file}:1:8: W: Unnecessary disabling of `Style/NumericLiterals`.
+            #{file}:1:26: C: Department name is missing.
             #{file}:1:41: C: Trailing whitespace detected.
           RESULT
         end
diff --git a/spec/rubocop/cli_spec.rb b/spec/rubocop/cli_spec.rb
index 807c412b7e3..1719f7ea83f 100644
--- a/spec/rubocop/cli_spec.rb
+++ b/spec/rubocop/cli_spec.rb
@@ -353,7 +353,9 @@ def and_with_args
         OUTPUT
         expect($stdout.string)
           .to eq(<<~RESULT)
+            #{abs('example.rb')}:3:110: C: Migration/DepartmentName: Department name is missing.
             #{abs('example.rb')}:4:81: C: Layout/LineLength: Line is too long. [95/80]
+            #{abs('example.rb')}:5:28: C: Migration/DepartmentName: Department name is missing.
         RESULT
       end
     end