I fibbed. I DID get charged for the SunPass tolls, but they went to another credit card over a month later. So it was $6/wk + tolls.

North Texas has no toll booths, Houston only has them on the Hardy Toll Road, and Austin has a few booths. Fortunately the North Texas tolltag is an interoperable one, so I can use it in all three areas.

Do you cover up your license plates too?

I spent a week in South Florida (Keys too) in December 2010. Rented a car from Enterprise. No mention of weekly rate for tolls so I just paid manual when needed. There was several times on tollways with construction that there was no manual lanes so I zoomed thru the sunpass lanes. Never heard from sunpass or enterprise and no additional charges appeared on my credit card (so far).

You really think the state of Florida cares where you travel to? If you're that worried about being tracked, what are you doing that you're not supposed to be doing?

Yes, it needs to be registered (as in you need to load money or have an account automatically withdraw funds), however, you can put it any car you want without registering every single vehicle and it works just fine. If you were to theoretically put in a fake plate number, the sunpass would still work. I use my sunpass all the time in rental vehicles (obviously not individually registered) and it works just fine.

It isn't just the state of Florida - all of these toll transponder units nationwide save your travel information and it can be handed over to the authorities without your consent, or provided to a civil litigant with a court order.

I don't need to prove that I'm not doing anything wrong in order to avoid being tracked. You do remember something called Liberty, right? How about privacy? I guard my privacy very carefully - no one needs to know where I've been or where I'm going.

The sticker transponders can only be put in one car and not moved or it will stop working.

I wasn't saying the stickers can be moved around, I was just saying even though it needs to be "registered", you can move the large transponder into "unregistered" vehicles....

You do know that even though you go through the pay in cash tolls, your license plate is on camera right? And if you go through a sunpass lane without a transponder it takes a photo of your plate and sends a bill to your address... so even if you're going through and paying cash, in theory your plate can still be tracked. Do you ever travel into Miami-dade county now cause it's sunpass only? Or would you just go out of your way and take 95?

Anyway, this is a pointless debate. You can be tracked anywhere at anytime.. a sunpass transponder is not going to make a difference.

To the main point, using a rental vehicle you won't get a transponder, however, you can use what's called their "plate pass" and it uses the license plate as a tool to track and pay the tolls... I believe Avis and Hertz regularly have plate-pass info stickers on the inside of the car to let you know how it works.. I know I've seen it in a couple companies cars, but I don't recall.. I only use national now, but I assume that's the way they all track it.. like I said before, I just use my regular sunpass and move it into the rental car so it doesn't use the plate and charge the rental company fee.

I'm headed to Miami in a few days and I'm sure I'll be driving a toll road. I recall hearing that most of them are now cashless. I was thinking of buying my own Sunpass (I recall you can get them in Publix and drugstores) but it sounds like I now MUST use National/Alamo's.

https://www.sunpass.com/rentalcar

Or are there certain lanes I could use my own? And if I just need Sunpass for 5 or so days a year, does it even make sense to own one?

I hate paying $2/day extra for something that it doesn't seem like I should have to pay for, but I'm also into practicality.

Thanks for the help.

I lived in FL for a few months a couple years back. In my personal vehicle I bought a SunPass at the first rest stop in the state. It may have changed since then (2009) but at that time registering a SunPass was NOT instantaneous. The process required calling in to fund the account, and took at least a day or two to go through.

So, with that in mind trying to buy your own SunPass for temporary use may not be the best idea.

They sell visitor sunpass at the rest stops. The last check it was preloaded with about $5 and could be refilled if necessary.

It's instantaneous now. I bought one in October or November 2012 to use on my rental car, registered it online on my iPhone, funded it with a credit card on my phone, even added the rental car's license plate to my account with an expiration date and time. Works great!

I just got back from Houston. They are definitely present on other roads. I remember there was quite a backup for the cash lanes on the Sam Houston Tollway west of IAH.

The problem with using the transponder on the rental car is the risk of double billing - money is taken from your transponder account and the rental car company may bill you for the toll as the system might submit a photo of the license tag anyway.

While the SunPass site says National charges only $2/day if you use a toll road, the fine print on my contract seemed to indicate that the rate was now $2.95 for every day of your rental, even if you only go through a single toll plaza on your entire trip.

As we only "needed" to go through 1 toll plaza our whole trip, we decided to avoid that plaza and save all the mandatory charges. This really is a sucky system for most folks, but when do muncipalities ever make things "good" for rental car customers?

Hmm, I was just looking at the fine print yesterday. Yeah, it was $2.95, but it also definitely said it was only charged on days that you generated a toll. Also had a maximum fee of $14.95 (obviously plus all the tolls).

Here's the fine print:
If you or any driver operate the rental vehicle in Northern California, Colorado, Florida, North Carolina, Texas, Washington State or British Columbia, Canada, and generate an unpaid toll, you will be charged our Toll Pass Convenience Charge of $2.95 for each day you use a toll road or bridge plus the cost of all unpaid tolls. The maximum TollPass Convenience Charge for the rental period is $14.75, plus the cost of all unpaid tolls. For information call (877) 860-1283. If you or any driver operate the rental vehicle in areas not served by TollPass and generate any unpaid toll(s) then you will be charged for all unpaid tolls and an administrative charge of up to $25.00 per rental.