diff --git a/test/test_helper.rb b/test/test_helper.rb
index 420fee2ef..040066c49 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -60,6 +60,15 @@ class ActiveSupport::TestCase
   self.use_transactional_tests = true
   self.use_instantiated_fixtures  = false
 
+  # Freeze the clock for the whole run so that fixtures (e.g. `1.minute.ago`)
+  # and tests share the same "now" even if the date changes mid-run.
+  FROZEN_TIME = Time.now
+
+  def before_setup
+    travel_to FROZEN_TIME
+    super
+  end
+
   setup do
     Redmine::SudoMode.stubs(:enabled?).returns(false)
   end