Yes, an E-ZPass can generally be used in another car, but there are important rules and limitations. The key factor is that the vehicle you use it in must be listed on your E-ZPass account. Most E-ZPass agencies allow you to register multiple vehicles (cars, motorcycles, even trailers) to a single transponder or account. However, if the transponder is not properly mounted or the vehicle is not registered, you risk fines for toll evasion, even if your account is in good standing.
The primary reason for registering vehicles is linked to your vehicle's classification, which determines the toll rate. Tolls are often calculated based on factors like the number of axles and vehicle height. Using a transponder registered to a passenger car in a large, multi-axle truck, for example, would result in underpaying the toll. For consistent use in a second car, the safest and most correct procedure is to add that vehicle's license plate number to your E-ZPass account online or by phone. This process is usually quick and free.
If you're only borrowing a car for a single trip, some agencies have a "trip pass" feature on their website where you can temporarily add a vehicle for a specific date range. If that's not an option, and you must use the transponder in an unregistered vehicle, ensure it is correctly mounted on the windshield. The toll will likely be deducted, but the transaction might be flagged for review. For occasional, infrequent use between two personally owned passenger cars, it often works without issue, but officially updating your account is always the recommended course of action to avoid potential problems.
