diff --git a/TrackingTools/TrackAssociator/src/TrackDetectorAssociator.cc b/TrackingTools/TrackAssociator/src/TrackDetectorAssociator.cc
index d7f9c41519024..d164292554f15 100644
--- a/TrackingTools/TrackAssociator/src/TrackDetectorAssociator.cc
+++ b/TrackingTools/TrackAssociator/src/TrackDetectorAssociator.cc
@@ -48,6 +48,7 @@
 #include "Geometry/CSCGeometry/interface/CSCGeometry.h"
 #include "Geometry/GEMGeometry/interface/GEMGeometry.h"
 #include "Geometry/GEMGeometry/interface/ME0Geometry.h"
+#include "Geometry/GEMGeometry/interface/GEMEtaPartitionSpecs.h"
 
 #include "TrackPropagation/SteppingHelixPropagator/interface/SteppingHelixPropagator.h"
 #include <stack>
@@ -665,6 +666,17 @@ void TrackDetectorAssociator::getTAMuonChamberMatches(std::vector<TAMuonChamberM
       float halfWidthAtYPrime = 0.5f * narrowWidth + yPrime * tangent;
       distanceX = std::abs(localPoint.x()) - halfWidthAtYPrime;
       distanceY = std::abs(localPoint.y() - yCOWPOffset) - 0.5f * length;
+    } else if (dynamic_cast<const GEMChamber*>(geomDet) || dynamic_cast<const GEMSuperChamber*>(geomDet)) {
+      const TrapezoidalPlaneBounds* bounds = dynamic_cast<const TrapezoidalPlaneBounds*>(&geomDet->surface().bounds());
+
+      float wideWidth = bounds->width();
+      float narrowWidth = 2.f * bounds->widthAtHalfLength() - wideWidth;
+      float length = bounds->length();
+      float tangent = (wideWidth - narrowWidth) / (2.f * length);
+      float halfWidthAtY = tangent * localPoint.y() + 0.5f * narrowWidth;
+
+      distanceX = std::abs(localPoint.x()) - halfWidthAtY;
+      distanceY = std::abs(localPoint.y()) - 0.5f * length;
     } else {
       distanceX = std::abs(localPoint.x()) - 0.5f * geomDet->surface().bounds().width();
       distanceY = std::abs(localPoint.y()) - 0.5f * geomDet->surface().bounds().length();