diff --git a/lib/redmine/i18n.rb b/lib/redmine/i18n.rb
index 83ecb05eb..5ece7592d 100644
--- a/lib/redmine/i18n.rb
+++ b/lib/redmine/i18n.rb
@@ -92,12 +92,12 @@ module Redmine
     def format_hours(hours)
       return "" if hours.blank?
 
+      minutes = (hours * 60).round
       if Setting.timespan_format == 'minutes'
-        h = hours.floor
-        m = ((hours - h) * 60).round
+        h, m = minutes.divmod(60)
         "%d:%02d" % [h, m]
       else
-        number_with_delimiter(sprintf('%.2f', hours.to_f), delimiter: nil)
+        number_with_delimiter(sprintf('%.2f', minutes / 60.0), delimiter: nil)
       end
     end
 
diff --git a/test/helpers/application_helper_test.rb b/test/helpers/application_helper_test.rb
index 70c112732..8cb086f12 100644
--- a/test/helpers/application_helper_test.rb
+++ b/test/helpers/application_helper_test.rb
@@ -2204,6 +2204,21 @@ class ApplicationHelperTest < Redmine::HelperTest
     end
   end
 
+  def test_format_hours_rounds_to_nearest_minute
+    set_language_if_valid 'en'
+
+    # 7h 59m 29s (7.991388888888889) -> 7h 59m (7.98)
+    # 7h 59m 30s (7.991666666666667) -> 8h  0m (8.00)
+    with_settings :timespan_format => 'minutes' do
+      assert_equal '7:59', format_hours(7.991388888888889)
+      assert_equal '8:00', format_hours(7.991666666666667)
+    end
+    with_settings :timespan_format => 'decimal' do
+      assert_equal '7.98', format_hours(7.991388888888889)
+      assert_equal '8.00', format_hours(7.991666666666667)
+    end
+  end
+
   def test_format_hours_should_use_locale_decimal_separator
     to_test = {'en' => '0.75', 'de' => '0,75'}
     with_settings :timespan_format => 'decimal' do