diff --git a/doc/user/Changelog.md b/doc/user/Changelog.md
index 404c27a9070..8e4b10a6f62 100644
--- a/doc/user/Changelog.md
+++ b/doc/user/Changelog.md
@@ -66,6 +66,7 @@ based on merged pull requests. Search GitHub issues and pull requests for smalle
 - Add Javadoc for Trip [#6022](https://github.com/opentripplanner/OpenTripPlanner/pull/6022)
 - Add Iceland to the list of deployments [ci skip] [#6057](https://github.com/opentripplanner/OpenTripPlanner/pull/6057)
 - Use correct HEAD request when fetching HTTP headers [#6063](https://github.com/opentripplanner/OpenTripPlanner/pull/6063)
+- Fix incorrect mapping of flex safe duration offset [#6059](https://github.com/opentripplanner/OpenTripPlanner/pull/6059)
 [](AUTOMATIC_CHANGELOG_PLACEHOLDER_DO_NOT_REMOVE)
 
 ## 2.5.0 (2024-03-13)
diff --git a/src/main/java/org/opentripplanner/gtfs/mapping/TripMapper.java b/src/main/java/org/opentripplanner/gtfs/mapping/TripMapper.java
index 3a62ba2b269..593c73f58d8 100644
--- a/src/main/java/org/opentripplanner/gtfs/mapping/TripMapper.java
+++ b/src/main/java/org/opentripplanner/gtfs/mapping/TripMapper.java
@@ -81,7 +81,7 @@ private Optional<TimePenalty> mapSafeTimePenalty(org.onebusaway.gtfs.model.Trip
     if (rhs.getSafeDurationFactor() == null && rhs.getSafeDurationOffset() == null) {
       return Optional.empty();
     } else {
-      var offset = Duration.ofSeconds(rhs.getSafeDurationOffset().longValue());
+      var offset = Duration.ofMinutes(rhs.getSafeDurationOffset().longValue());
       return Optional.of(TimePenalty.of(offset, rhs.getSafeDurationFactor().doubleValue()));
     }
   }
diff --git a/src/test/java/org/opentripplanner/gtfs/mapping/TripMapperTest.java b/src/test/java/org/opentripplanner/gtfs/mapping/TripMapperTest.java
index 964c3d8155e..c438fb2fd06 100644
--- a/src/test/java/org/opentripplanner/gtfs/mapping/TripMapperTest.java
+++ b/src/test/java/org/opentripplanner/gtfs/mapping/TripMapperTest.java
@@ -6,6 +6,7 @@
 import static org.junit.jupiter.api.Assertions.assertSame;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
+import java.time.Duration;
 import java.util.Collection;
 import java.util.Collections;
 import org.junit.jupiter.api.Test;
@@ -122,12 +123,12 @@ void flexTimePenalty() {
     var flexTrip = new Trip();
     flexTrip.setId(new AgencyAndId("1", "1"));
     flexTrip.setSafeDurationFactor(1.5);
-    flexTrip.setSafeDurationOffset(600d);
+    flexTrip.setSafeDurationOffset(60d);
     flexTrip.setRoute(new GtfsTestData().route);
     var mapper = defaultTripMapper();
     var mapped = mapper.map(flexTrip);
     var penalty = mapper.flexSafeTimePenalties().get(mapped);
     assertEquals(1.5f, penalty.coefficient());
-    assertEquals(600, penalty.constant().toSeconds());
+    assertEquals(Duration.ofHours(1), penalty.constant());
   }
 }