diff --git a/instrumentation/all/lib/opentelemetry/instrumentation/all.rb b/instrumentation/all/lib/opentelemetry/instrumentation/all.rb
index 93fde7e84..7426060f6 100644
--- a/instrumentation/all/lib/opentelemetry/instrumentation/all.rb
+++ b/instrumentation/all/lib/opentelemetry/instrumentation/all.rb
@@ -11,6 +11,7 @@
 require 'opentelemetry-instrumentation-active_job'
 require 'opentelemetry-instrumentation-active_record'
 require 'opentelemetry-instrumentation-action_view'
+require 'opentelemetry-instrumentation-action_mailer'
 require 'opentelemetry-instrumentation-aws_sdk'
 require 'opentelemetry-instrumentation-bunny'
 require 'opentelemetry-instrumentation-lmdb'
diff --git a/instrumentation/rails/lib/opentelemetry/instrumentation/rails.rb b/instrumentation/rails/lib/opentelemetry/instrumentation/rails.rb
index ce8ee826b..f421f3a29 100644
--- a/instrumentation/rails/lib/opentelemetry/instrumentation/rails.rb
+++ b/instrumentation/rails/lib/opentelemetry/instrumentation/rails.rb
@@ -18,6 +18,7 @@ module Rails
 require 'opentelemetry-instrumentation-action_pack'
 require 'opentelemetry-instrumentation-active_support'
 require 'opentelemetry-instrumentation-action_view'
+require 'opentelemetry-instrumentation-action_mailer'
 require 'opentelemetry-instrumentation-active_record'
 require_relative 'rails/instrumentation'
 require_relative 'rails/version'
diff --git a/instrumentation/rails/opentelemetry-instrumentation-rails.gemspec b/instrumentation/rails/opentelemetry-instrumentation-rails.gemspec
index 6a97e5bb7..33a50bcf0 100644
--- a/instrumentation/rails/opentelemetry-instrumentation-rails.gemspec
+++ b/instrumentation/rails/opentelemetry-instrumentation-rails.gemspec
@@ -26,6 +26,7 @@ Gem::Specification.new do |spec|
   spec.required_ruby_version = '>= 3.0'
 
   spec.add_dependency 'opentelemetry-api', '~> 1.0'
+  spec.add_dependency 'opentelemetry-instrumentation-action_mailer', '~> 0.1.0'
   spec.add_dependency 'opentelemetry-instrumentation-action_pack', '~> 0.9.0'
   spec.add_dependency 'opentelemetry-instrumentation-action_view', '~> 0.7.0'
   spec.add_dependency 'opentelemetry-instrumentation-active_job', '~> 0.7.0'