diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 12481823..268321c8 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -10,13 +10,6 @@ jobs:
         ruby: [ head, '3.1', '3.0', '2.7' ]
         os: [ ubuntu-latest, macos-latest ]
         experimental: [false]
-        include:
-#          - ruby: 2.6
-#            os: ubuntu-latest
-#            experimental: true
-          - ruby: 2.6
-            os: macos-latest
-            experimental: false
     runs-on: ${{ matrix.os }}
     continue-on-error: ${{ matrix.experimental }}
     steps:
diff --git a/net-imap.gemspec b/net-imap.gemspec
index 6b791c86..298a8f5f 100644
--- a/net-imap.gemspec
+++ b/net-imap.gemspec
@@ -16,7 +16,7 @@ Gem::Specification.new do |spec|
   spec.summary       = %q{Ruby client api for Internet Message Access Protocol}
   spec.description   = %q{Ruby client api for Internet Message Access Protocol}
   spec.homepage      = "https://github.com/ruby/net-imap"
-  spec.required_ruby_version = Gem::Requirement.new(">= 2.6.0")
+  spec.required_ruby_version = Gem::Requirement.new(">= 2.7.0")
   spec.licenses       = ["Ruby", "BSD-2-Clause"]
 
   spec.metadata["homepage_uri"] = spec.homepage