diff --git a/CHANGELOG.md b/CHANGELOG.md
index 43cc3e1..4ef6de9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,8 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## Unreleased
 
 ## 6.0.0 - 2024-07-04
-### Changed
-- Removed support for Rollbar configuration.
+### BREAKING CHANGE
+- Removed support for Rollbar configuration. `config.rollbar` is no longer supported.
 - Added support for passing `error_reporting_func` as a config option.
 
 ## 5.3.4 - 2024-06-14
diff --git a/lib/pheme/configuration.rb b/lib/pheme/configuration.rb
index 276547b..8ddcef2 100644
--- a/lib/pheme/configuration.rb
+++ b/lib/pheme/configuration.rb
@@ -24,6 +24,10 @@ class Configuration
     def initialize
       @logger ||= Logger.new($stdout) # rubocop:disable Lint/DisjunctiveAssignmentInConstructor
       @logger = ActiveSupport::TaggedLogging.new(@logger) unless @logger.respond_to?(:tagged)
+
+      if respond_to?(:rollbar)
+        ActiveSupport::Deprecation.warn("config.rollbar is deprecated. Please use config.error_reporting_func instead.")
+      end
     end
 
     def validate!