diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index fd8af93..00bc3f6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,32 +11,22 @@ jobs:
       fail-fast: false
       matrix:
         ruby: [3.2, 3.1, '3.0', 2.7, 2.6, ruby-head]
-        rails: ['7.0.0', '6.1.0', '6.0.0', '5.2.0', main]
+        rails: ['7.0.0', '6.1.0', '6.0.0', main]
         exclude:
           - ruby: ruby-head
             rails: '6.1.0'
           - ruby: ruby-head
             rails: '6.0.0'
-          - ruby: ruby-head
-            rails: '5.2.0'
           - ruby: 3.2
             rails: '6.0.0'
-          - ruby: 3.2
-            rails: '5.2.0'
           - ruby: 3.1
             rails: '6.0.0'
-          - ruby: 3.1
-            rails: '5.2.0'
           - ruby: 3.0
             rails: main
           - ruby: 3.0
             rails: '6.0.0'
-          - ruby: 3.0
-            rails: '5.2.0'
           - ruby: 2.7
             rails: main
-          - ruby: 2.7
-            rails: '5.2.0'
           - ruby: 2.6
             rails: main
           - ruby: 2.6
diff --git a/Gemfile b/Gemfile
index fe1f9bc..2739fe4 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,7 +6,7 @@ rails =
   when 'main'
     { github: 'rails/rails' }
   when 'default'
-    '>= 5.0'
+    '>= 6.0'
   else
     "~> #{ENV['RAILS_VERSION']}"
   end
diff --git a/jsonapi-rails.gemspec b/jsonapi-rails.gemspec
index 24c4a45..84bbd7e 100644
--- a/jsonapi-rails.gemspec
+++ b/jsonapi-rails.gemspec
@@ -19,7 +19,7 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'jsonapi-rb', '~> 0.5.0'
   spec.add_dependency 'jsonapi-parser', '~> 0.1.0'
 
-  spec.add_development_dependency 'rails', '>= 5.0'
+  spec.add_development_dependency 'rails', '>= 6.0'
   spec.add_development_dependency 'sqlite3', '>= 1.3'
   spec.add_development_dependency 'rake',        '>= 11.3'
   spec.add_development_dependency 'rspec-rails', '>= 4.0'
diff --git a/spec/dummy/config/initializers/new_framework_defaults.rb b/spec/dummy/config/initializers/new_framework_defaults.rb
index 69c499f..9359584 100644
--- a/spec/dummy/config/initializers/new_framework_defaults.rb
+++ b/spec/dummy/config/initializers/new_framework_defaults.rb
@@ -17,10 +17,5 @@
 # Require `belongs_to` associations by default. Previous versions had false.
 Rails.application.config.active_record.belongs_to_required_by_default = true
 
-# Do not halt callback chains when a callback returns false. Previous versions had true.
-if Rails.version < '5.2'
-  ActiveSupport.halt_callback_chains_on_return_false = false
-end
-
 # Configure SSL options to enable HSTS with subdomains. Previous versions had false.
 Rails.application.config.ssl_options = { hsts: { subdomains: true } }
diff --git a/spec/dummy/config/initializers/sqlite3_fix.rb b/spec/dummy/config/initializers/sqlite3_fix.rb
index 53f9423..a09345e 100644
--- a/spec/dummy/config/initializers/sqlite3_fix.rb
+++ b/spec/dummy/config/initializers/sqlite3_fix.rb
@@ -1,3 +1,3 @@
-if Rails.version >= '5.1.0' && Rails.application.config.active_record.sqlite3.present?
+if Rails.application.config.active_record.sqlite3.present?
   Rails.application.config.active_record.sqlite3.represent_boolean_as_integer = true
 end