diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 0a3168489..96135e135 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -16,10 +16,6 @@ jobs:
       fail-fast: false
       matrix:
        include:
-         - ruby: 2.5
-           timeout: 5
-         - ruby: 2.6
-           timeout: 5
          - ruby: 2.7
            timeout: 5
          - ruby: '3.0'
@@ -30,19 +26,17 @@ jobs:
            timeout: 5
          - ruby: 3.3
            timeout: 5
+         - ruby: head
+           timeout: 5
          - ruby: truffleruby
            timeout: 50
          - ruby: truffleruby-head
            timeout: 50
-         - ruby: jruby
-           timeout: 5
-         - ruby: jruby-head
-           timeout: 5
          - ruby: jruby-9.4
            timeout: 5
-         - ruby: jruby-9.3
+         - ruby: jruby
            timeout: 5
-         - ruby: jruby-9.2
+         - ruby: jruby-head
            timeout: 5
     steps:
     - name: Installing libyaml-dev
diff --git a/Gemfile b/Gemfile
index aaed6fd11..0ad7c61dd 100644
--- a/Gemfile
+++ b/Gemfile
@@ -3,15 +3,9 @@ source 'https://rubygems.org'
 gemspec
 
 if ENV['MBCHARS'] # see spec/environment.rb
-  if RUBY_VERSION < '2.7.0'
-    gem 'activesupport', '< 6'
-  else
-    gem 'activesupport', :git => 'https://github.com/rails/rails', :branch => 'main'
-  end
+  gem 'activesupport', :git => 'https://github.com/rails/rails', :branch => 'main'
 end
 
 gem 'jruby-openssl', :platforms => :jruby
 
-gem 'mini_mime'
-
 gem 'byebug', :platforms => :mri
diff --git a/README.md b/README.md
index dd0237501..b2ef0487c 100644
--- a/README.md
+++ b/README.md
@@ -49,14 +49,12 @@ our documentation, add new features—up to you! Thank you for pitching in.
 
 Mail is tested against:
 
-* Ruby: 2.5
-* Ruby: 2.6
 * Ruby: 2.7
 * Ruby: 3.0
 * Ruby: 3.1
 * Ruby: 3.2
-* JRuby: 9.2
-* JRuby: 9.3
+* Ruby: 3.3
+* Ruby: head
 * JRuby: 9.4
 * JRuby: stable
 * JRuby: head
diff --git a/mail.gemspec b/mail.gemspec
index 59561769d..9de665d12 100644
--- a/mail.gemspec
+++ b/mail.gemspec
@@ -13,7 +13,7 @@ Gem::Specification.new do |s|
   s.extra_rdoc_files = %w[ README.md ]
   s.rdoc_options << '--exclude' << 'lib/mail/values/unicode_tables.dat'
 
-  s.required_ruby_version = ">= 2.5"
+  s.required_ruby_version = ">= 2.7"
 
   s.add_dependency('mini_mime', '>= 0.1.1')
   s.add_dependency('net-smtp')