diff --git a/Sources/mParticle-Appboy/MPKitAppboy.m b/Sources/mParticle-Appboy/MPKitAppboy.m
index 7767c35..ef8d690 100644
--- a/Sources/mParticle-Appboy/MPKitAppboy.m
+++ b/Sources/mParticle-Appboy/MPKitAppboy.m
@@ -650,6 +650,8 @@ - (MPKitExecStatus *)setUserAttribute:(NSString *)key value:(NSString *)value {
 #endif
     } else if ([key isEqualToString:mParticleUserAttributeMobileNumber] || [key isEqualToString:@"$MPUserMobile"]) {
         appboyInstance.user.phone = value;
+    } else if ([key isEqualToString:mParticleUserAttributeZip]){
+        [appboyInstance.user setCustomAttributeWithKey:@"Zip" andStringValue:value];
     } else {
         key = [self stripCharacter:@"$" fromString:key];