Originally Posted by
chrisl137
Massachusetts instructions say to
add the rental car to your account, but I've used my own EZPass a bunch of times there without problems and without getting double billed. I live in CA, but have an MA EZPass that's registered to my CA license plate and address. It's only ever been used in rental cars.
ETA: my solution to leaving it in the rental car is to tie a thin, bright colored string to it that hangs below the mirror. I put enough string on it that I can attach it t a carabiner on my backpack in the passenger seat. I only just started doing the string after I left it in the car in December, after years of not forgetting it. Fortunately I had a ton of time before my flight and had time to take the shuttle back to Hertz and wait around while they found my car and the transponder (I wrote them a very nice review for that)
I have a MA EZ-Pass too (also registered to my CA car that will probably never be near such a toll :-) and always add rental car plates to the account. It's pretty quick to do, allows for an end date/time, and covers you in case the transponder doesn't read for whatever reason. I can verify that one trip I didn't even have the transponder (couldn't find it when packing), and all of the tolls (MA tolls in this case but shouldn't matter) properly got charged to my account.
It's pretty obnoxious that NY and some others *don't* let you overlay your account on a registered plate. This should be basic standardized functionality for electronic tolls if the desire is to be traveler-friendly, but I suspect the rental toll "service" companies have some influence and like it the way it is so they can collect their outrageous fees.