What a SunPass Mini is and why you need one

A SunPass Mini is a small electronic transponder that mounts inside your vehicle and automatically pays tolls on Florida's toll roads. When you drive through a toll plaza, the transponder communicates with overhead readers, deducting the toll amount from your prepaid account. You do not stop, roll down a window, or hand anyone money — the system reads your transponder and charges you when ready.

If you drive on Florida's Turnpike, I-75, I-95, the Beachline Expressway, or any of the state's other toll roads regularly, a SunPass Mini saves time and money. The transponder costs nothing to obtain, and you typically pay a lower per-toll rate than drivers who pay cash at a booth. The device itself is about the size of a deck of cards and runs on a battery that lasts roughly six to eight years.

Key Takeaways

  • Order your free SunPass Mini from sunpass.com or by calling 1-888-SUNPASS, then set up a prepaid account with a credit or debit card before the device arrives.
  • Mount the transponder on your windshield between the rearview mirror and the side window, in the upper third of the glass, using the adhesive strip that comes with it.
  • Your account balance must be at least $10 before you use the transponder on toll roads, or tolls will not be deducted and you may receive a violation notice.
  • Test your transponder by driving through a toll plaza at normal speed; if the overhead light turns green, your transponder is reading correctly.
  • If tolls are not being deducted or you see error messages, log into your SunPass account online or call customer service to check your account status and transponder registration.

Ordering your SunPass Mini and setting up your account

Visit sunpass.com and click "Order a Transponder" or call 1-888-SUNPASS (1-888-786-7277) to request a free SunPass Mini. You will need your vehicle's license plate number and the state it is registered in. The website will ask whether you want a standard SunPass account or a SunPass PRO account — most drivers choose standard, which charges you per toll used. SunPass PRO is for high-volume users and requires a monthly subscription.

After you request the transponder, you must create a prepaid account before the device arrives. Log into your new SunPass account at sunpass.com using the confirmation number from your order. Add a credit card or debit card as your payment method, then deposit at least $10 into your account balance. This money sits in your account and is deducted each time you pass through a toll plaza. The transponder itself will arrive by mail within 7 to 10 business days.

Do not wait until after the transponder arrives to fund your account. If you drive through a toll plaza with an unfunded or unregistered transponder, the toll will not be deducted, and you may receive a violation notice in the mail weeks later. Funding your account before installation prevents this problem.

Mounting the transponder on your windshield

When your SunPass Mini arrives, you will find the transponder itself, an adhesive mounting strip, and an instruction sheet. Choose a location on your windshield in the upper third of the glass, between your rearview mirror and the driver's side window. This placement keeps the transponder in the reader's line of sight and away from areas where you might accidentally damage it.

Clean the windshield in that spot with a dry cloth to remove dust and moisture. Peel the backing off the adhesive strip and press it firmly onto the back of the transponder. Then peel the second backing layer and press the transponder onto the windshield, holding it in place for 10 to 15 seconds. The adhesive takes about 24 hours to cure fully, so avoid driving through toll plazas until the next day if possible.

Do not mount the transponder on your dashboard, on the outside of your vehicle, or behind a tinted window film. These placements prevent the overhead readers from detecting the signal. If you remove the transponder later to transfer it to another vehicle, you can peel it off carefully — the adhesive will not damage the windshield, though it may leave a faint residue that rubbing alcohol removes.

Registering your transponder and testing it

After you mount the transponder, log back into your SunPass account at sunpass.com and confirm that your transponder is registered to your vehicle. The system should show your license plate number and the transponder's serial number (printed on the device). If the registration does not appear within a few hours, call 1-888-SUNPASS to verify it manually.

Once registration is complete and your account has at least $10, drive through any toll plaza at normal highway speed. As you approach the toll booth area, look for an overhead light above your lane. If the light turns green, your transponder is communicating with the reader and your toll has been deducted. If the light turns red or does not light up, your transponder may not be registered correctly or your account may not be funded.

Check your SunPass account online within a few hours of passing through the toll plaza. You should see the toll amount deducted from your balance. If the toll does not appear, or if you see a violation notice in your account, contact SunPass customer service when ready to troubleshoot the problem.

Maintaining your account and monitoring your balance

Your SunPass account will automatically deduct tolls each time you pass through a toll plaza. When your balance drops below $10, the system will stop deducting tolls to prevent your account from going negative. You will receive an email notification when your balance is low, and tolls will not be charged until you add more money.

Log into sunpass.com regularly to check your balance and transaction history. You can set up automatic replenishment so that money is added to your account automatically when the balance falls below a certain amount — this prevents you from being caught with an unfunded account at a toll plaza. Add money using a credit card, debit card, or bank account transfer.

If you sell your vehicle or transfer the transponder to a different car, log into your account and update your license plate number. If you do not update it, tolls may not be deducted correctly, or you may receive violation notices for the old vehicle. You can also contact SunPass customer service to make changes over the phone.

Troubleshooting common problems

If tolls are not being deducted from your account, first check that your account balance is at least $10 and that your transponder is registered to the correct vehicle. Log into sunpass.com and verify both pieces of information. If your balance is low, add money when ready and try again at the next toll plaza.

If your transponder is registered and your account is funded but tolls still are not being deducted, the transponder itself may be faulty or the adhesive mounting may have failed. Check that the transponder is still firmly attached to your windshield. If it has come loose, clean the windshield again and remount it with a new adhesive strip (you can order replacement strips from sunpass.com).

If you see a violation notice in your account for a toll that should have been deducted, contact SunPass customer service at 1-888-SUNPASS with your account number and the date of the toll. Explain that your transponder was mounted and your account was funded. Customer service can investigate whether the transponder failed to read and may reverse the violation charge.

If your transponder stops working after several years, the battery has likely expired. Order a replacement transponder from sunpass.com at no charge, mount it on your windshield, and update your account registration. Your account balance and transaction history will transfer automatically to the new transponder.

What happens if you drive through a toll plaza without a working transponder

If you pass through a toll plaza without a working transponder or without funding your account, the overhead camera photographs your license plate. The toll authority mails you a violation notice weeks later, charging you the toll amount plus a processing fee. This fee varies but is typically $2.50 to $5.00 per violation.

If you receive a violation notice, you can pay it online, by mail, or by phone using the information on the notice. You can also dispute it if you believe your transponder was working correctly — contact the toll authority listed on the notice with proof that your account was funded and your transponder was registered at the time of the toll.

To avoid violations, always may support your account has at least $10 before driving on toll roads. If your transponder fails, contact SunPass customer service when ready to report the problem and request a replacement.

Frequently Asked Questions

Can I use my SunPass Mini in another state?

SunPass works only on Florida toll roads. If you travel to other states with toll roads, you will need a separate transponder for that state — for example, E-ZPass in the Northeast or FasTrak in California. Some states have reciprocal agreements with Florida, but you cannot use a single SunPass transponder across state lines.

What if I want to use the same transponder in multiple vehicles?

You can transfer your transponder between vehicles, but you must update your license plate number in your SunPass account each time you switch cars. Log into sunpass.com and change the registered plate number before driving on toll roads in the different vehicle. If you do not update it, tolls may not be deducted correctly.

Does my SunPass Mini work if I have a tinted windshield?

Heavy window tint can block the signal between your transponder and the overhead reader. If your windshield is heavily tinted, mount the transponder as high as possible and as close to the center as you can. If tolls still are not being deducted, contact SunPass customer service — they may be able to adjust your account or provide a different mounting solution.

What if my account balance goes negative?

Your SunPass account will not allow tolls to be deducted if your balance is below $10. If you somehow end up with a negative balance, you will receive a notice in the mail or an email asking you to pay the amount owed. Add money to your account when ready to bring it back to a positive balance and resume using your transponder.

Can I get a refund if I no longer need my SunPass account?

Yes. Log into sunpass.com and request to close your account, or call 1-888-SUNPASS. Any remaining balance in your account will be refunded to the credit card or bank account you used to fund it, typically within 7 to 10 business days. You can keep the transponder or dispose of it — it will no longer work once your account is closed.