diff --git a/nav2_regulated_pure_pursuit_controller/src/regulated_pure_pursuit_controller.cpp b/nav2_regulated_pure_pursuit_controller/src/regulated_pure_pursuit_controller.cpp
index d8721c646f..55898dc339 100644
--- a/nav2_regulated_pure_pursuit_controller/src/regulated_pure_pursuit_controller.cpp
+++ b/nav2_regulated_pure_pursuit_controller/src/regulated_pure_pursuit_controller.cpp
@@ -802,7 +802,7 @@ bool RegulatedPurePursuitController::transformPose(
 double RegulatedPurePursuitController::getCostmapMaxExtent() const
 {
   const double max_costmap_dim_meters = std::max(
-    costmap_->getSizeInMetersX(), costmap_->getSizeInMetersX());
+    costmap_->getSizeInMetersX(), costmap_->getSizeInMetersY());
   return max_costmap_dim_meters / 2.0;
 }