2 files changed, 7 insertions, 3 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_definitions.rb
index 617b5c35bd..4afb4733eb 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/schema_definitions.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_definitions.rb
@@ -44,8 +44,12 @@ module ActiveRecord
         def primary_key(name, type = :primary_key, **options)
           if type == :uuid
             options[:default] = options.fetch(:default, "gen_random_uuid()")
-          elsif options.delete(:auto_increment) == true && type == :integer
-            type = :serial
+          elsif options.delete(:auto_increment) == true && %i(integer bigint).include?(type)
+            type = if type == :bigint || options[:limit] == 8
+              :bigserial
+            else
+              :serial
+            end
           end
 
           super
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/sqlite3/schema_definitions.rb
index 5d1e8811f8..d0b38dff4c 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3/schema_definitions.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3/schema_definitions.rb
@@ -3,7 +3,7 @@ module ActiveRecord
     module SQLite3
       module ColumnMethods
         def primary_key(name, type = :primary_key, **options)
-          if options.delete(:auto_increment) == true && type == :integer
+          if options.delete(:auto_increment) == true && %i(integer bigint).include?(type)
             type = :primary_key
           end