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How the Express Lanes Work

How the Express Lanes Work

UDOT’s Express Lanes, located on I-15 between Riverdale and Spanish Fork, maximize speed and reliability for carpoolers, motorcyclists, and solo drivers who pay a toll. The Express Lanes reduce congestion in all I-15 lanes by offering dedicated space to these users. 

Use of the Express Lanes by drivers who don’t meet one of the requirements is illegal. Keep in mind that:

  • Speed limits still apply
  • The Express Lanes should not be used to pass other vehicles
  • Crossing the double white lines is not only illegal – it is unsafe!

Use the Express Lanes while Carpooling

If you only use the Express Lanes when carpooling, you’re in luck! Simply use the Express Lanes when you have another person in your vehicle and you won’t be charged. 

Use an Express Pass when Driving Alone

Solo drivers can use the Express Lanes by purchasing an Express Pass, which is a small radio frequency transponder that you mount to your windshield behind the rear-view mirror. The I-15 Express Lanes are divided into payment zones with overhead signs that show the price to use each zone. This price increases when the Express Lanes are more congested to maintain speed and reliability in the lanes.

Readers at several locations along the Express Lanes detect your Express Pass as you travel through each zone and charge your account when you exit. You will only pay the price shown when you entered each zone. Pricing ranges from $0.25 cents to $2 per zone depending on congestion. Costs are highest during peak traffic times to discourage too many drivers from entering the lanes.

Please note: Additional fees apply to set up and maintain your Express Pass account. In addition to the initial setup costs, Express Pass account holders are charged an account maintenance fee each month if the account does not accrue at least $2.50 in tolls. (This $2.50 account maintenance fee is reduced by tolls charged during a month up to a total removal of the fee when $2.50 in tolls is reached.)

Check out our FAQs to learn more about where to mount and how to use the Express Pass.

Mixing Carpooling and Driving Alone

Express Pass owners can still ride free as a carpooler. Move the slider to the HOV (high-occupancy vehicle) position, and the toll system will recognize your vehicle as HOV and not charge a toll to your account.

Image of Express Lanes Express Pass transponder in HOV mode
Image of Express Lanes Express Pass transponder in HOV mode

Requirements to Use the Express Lanes

How you’re drivingRequirements
Driving aloneExpress Pass in TOLL mode
Carpooling (2 or more occupants
in a vehicle)
No Pass required OR
Express Pass in HOV mode
MotorcycleNo Pass required
BusNo Pass required
Clean Fuel VehicleClean Vehicle Pass

Violating these requirements (such as solo driving in the lane alone without an Express Pass in TOLL mode) could result in a fine of $337 or more.

Vehicles not Allowed in the Express Lanes

  • Vehicles with a gross vehicle weight greater than 12,000 lbs
  • Vehicles pulling trailers
  • Solo drivers without an Express Pass in TOLL mode or valid Clean Vehicle Permit, Pass, and sticker

Know the Signs

Express Lanes VTMS Message: 25 cent toll

The amount shown on the sign you see just before you enter the Express Lanes is the cost to drive in the zone, even if the price changes while you are still in the zone. The costs to drive in each zone ranges from $0.25 to $2 depending on congestion levels.

Express Lanes VTMS Message: FREE

All drivers, carpoolers or solo drivers, can use the Express Lanes for free. You may see this when there is a planned construction closure in another I-15 lane, or when a crash or other incident is blocking the other lanes.

Express Lanes VTMS Message: CLOSED

All drivers must exit the Express Lanes at the next access point. You may see this if there is a planned construction closure of the Express Lanes, or a crash or other incident blocking the Express Lanes.


Frequently Asked Questions

About the Express Lanes

    What are the Express Lanes?

    The Express Lanes is a single lane, in each direction of I-15, that extends for 72 miles from Spanish Fork to Layton. The Express Lanes system uses electronic toll plazas to read the Express Passes to apply a toll to prepaid accounts. The toll for accessing the Express Lanes increases in congested times to maintain lane performance and maximize freeway efficiency by encouraging carpools. Vehicles can enter or leave the lane at striped accesses at every interchange.

    Who can use the Express Lanes?

    The following vehicles can use the Express Lanes
    • Passenger vehicles with more than one person
    • Passenger vehicles with one person and an Express Pass in Toll mode or a Clean Vehicle Pass
    • Buses and motorcycles
    Vehicles not allowed in the Express Lanes:
    • Vehicles over 12,000 Gross Vehicle Weight
    • Trailers

    Why can't my Pass be read through my windshield?

    Some vehicles include additional shielding built into their windshield to prevent electronic interference with onboard computers. This shielding can prevent the toll system from reading your Express Pass, which uses RFID technology to communicate with the roadside tolling equipment. Common models that experience issues include plug-in hybrid vehicles, electric vehicles, and vehicles with heated windshields. Vehicle owners should consult their owner’s manual for mounting locations appropriate to their vehicle.

    Where can I enter and exit the Express Lanes?

    Express Lanes users may enter and exit the lanes at access points marked by dashed white lines. An access point is located at most interchanges. Users should exit the Express Lanes at the interchange before their exit. Signs along the Express Lanes indicate which access point to use to reach your exit safely. In some traffic conditions, it may be necessary to exit sooner.

    What about rules for moving over for vehicles behind me?

    Utah state code regarding moving over for vehicles in the left lane only applies to “general purpose” lanes, which the Express Lane is not. Speed limits, and all other laws and regulations still apply while in the Express Lanes.

    What do the indicator lights on the barrier mean?

    The lights on the barrier show the status of each vehicle that travels under signs displaying the tolls.
    • Green indicates an Express Pass was read and a toll charged. All vehicles with one occupant should show this indication.
    • Yellow indicates the vehicle does not have an Express Pass or that an Express Pass wasn’t read and law enforcement should check if the driver is carpooling. Only vehicles with two or more occupants, buses, or motorcycles should show this indication.
    • Blue indicates that the Express Pass is invalid. If you see this color when you drive in the Express Lanes, contact a customer service representative.

About the Express Pass

    What is an Express Pass?

    An Express Pass is a toll transponder with a switch to change between Toll and HOV mode. Toll mode should be used to pay and toll when driving alone. HOV mode should be used when vehicles have two or more passengers to receive the toll discount. The Express Pass should be mounted to the inside of the vehicle’s windshield. [Link to instructions] Readers at located with the overhead signs that display the toll price. The readers detect your Express Pass as you travel through each zone and charge your account when you exit the Express Lanes. The tolls displayed on the plazas reflect the cost to drive in the next segment. Drivers are only charged once per zone. Pricing ranges from $0.25 cents to $2 per zone depending on congestion. For more information or to get a pass, access the Get a Pass page.

    How much does an Express Pass cost?

    An Express Pass costs $9.65 plus tax and shipping. Your Express Pass prepaid account must have a balance between $10 and $35 per Express Pass. Each Express Pass account is charged a monthly $2.50 administrative fee per Express Pass for account maintenance. The fee is waived if more than $2.50 in tolls were charged the previous month, otherwise the fee is reduced by the amount of tolls charged in the previous month. For example, if the Express Pass incurred $1.00 in tolls the previous month, that month’s administrative fee would be $1.50.

    Can I use my Express Pass in more than one vehicle?

    Yes. The Express Pass can be moved from one vehicle to another. We recommend that you purchase a holder for each vehicle in which you plan to use your Express Pass.

    How is the toll determined?

    The Express Lanes are divided into seven payment zones in each direction with overhead signs that show the current price to travel in each zone. The system manages capacity in the lanes using a supply-and-demand concept. An algorithm adjusts the price in each zone based on congestion. Costs are higher during peak traffic. Higher costs are designed to discourage too many drivers from entering the lanes when the lanes are full, resulting in higher speeds for carpoolers and drivers when they need it. Pricing per zone ranges from $0.25 cents to $2 per zone depending on congestion.

    How long does it take to get an Express Pass?

    Your Express Pass should arrive 7 to 10 business days from when you open an account.

    How do I install my Express Pass?

    The Express Pass should be mounted on the inside of the vehicle windshield. Follow these installation instructions.

Managing Your Express Pass Account

    How does my Express Pass account work?

    When you set up an Express Pass account, $25.00 is prepaid into your account. Tolls are deducted from the account a few hours after completing a trip in the Express Lanes. When the account balance falls below $10.00, another $25.00 is added to your prepaid balance using the payment card on your account. For accounts with multiple passes, the payment card will be initially charged $25 for each Express Pass. When an Express Pass is used, the toll is deducted from the account balance. The minimum balance allowed on the account is $10 per pass. When the account balance drops below the minimum, the payment card will be charged $25 for each Express Pass on the account. For example, accounts with three passes have a minimum balance of $30 and will have $75 added every time the balance drops below $30.

    How do I update my Express Pass Account?

    You can update your account information online or by calling customer service at 855-813-9127. When you open an Express Pass account you are required to keep your name, email address, address phone number, and credit card information current.

About the Clean Vehicle Program

    Do ‘Clean Vehicles’ automatically qualify to drive in the Express Lane?

    NNo. Clean Vehicles are required to apply for, and have received and installed Clean Vehicle Pass or Express Pass, or be HOV status, in order to use the lane. All vehicles, regardless of fuel type, are not allowed to use the Express Lanes without a valid pass or without carpooling.

    What vehicles qualify for the Clean Vehicle Program?

    Plug-in hybrids, Electric, and alternative fuel vehicles registered in the State of Utah typically qualify for the Clean Vehicle Program. Review the list of qualifying used & new electric or plug-in vehicles or alternative fuel vehicles.

    What does it cost to get a Clean Vehicle Pass?

    If your vehicle qualifies for a Clean Vehicle Permit you will be charged a $10.00 processing fee to receive the Clean Vehicle Permit, Clean Vehicle Pass, and Clean Vehicle Sticker.

    Can I move my Clean Vehicle Pass to another vehicle or a new windshield?

    No. The Pass will be damaged when it is removed from your windshield. See instructions for replacing a Clean Vehicle Pass or transferring a Pass to a new vehicle on the Get a Pass page.

    What should I do when I sell my vehicle?

    Remove the Clean Vehicle Permit, Pass, and External sticker from your vehicle before selling your vehicle. If you purchase or plan to purchase an eligible vehicle you can apply to transfer the Clean Vehicle Pass to the new vehicle.

    How do I install my Clean Vehicle Permit, Pass, and Sticker?

    Follow these installation instructions after receiving your Clean Vehicle Permit, Pass, and Sticker. The Permit is a certification document that includes owner and vehicle information and should be carried in the vehicle at all times to present to an officer upon request. The Clean Vehicle Pass is a sticker transponder that is placed on a vehicle’s windshield to the right of the rear-view mirror. The Sticker is an external decal that is placed on the back of the vehicle.

    How long will it take to get my Clean Vehicle Pass?

    Note that the Clean Vehicle program is capped at 6,650 vehicles. We are currently experiencing extreme queue times, while the program is set to sunset in September of 2025. New applicants are not likely to receive a Clean Vehicle Pass before the expiration of the program. Current applicants can check their application status at https://udottraffic.utah.gov/CDecal/ by clicking the green “Status Check” button near the top of the page.

    Why is there a cap on vehicles?

    The Clean Vehicle Pass program was designed to use excess capacity in the Express Lanes to encourage the adoption of clean fuel types to reduce emissions. The cap of 6,650 Clean Vehicle Passes has been instituted to ensure the lane functions correctly for HOV and toll users.

    Do I have to pay $10 annually?

    There are no additional fees or charges other than the initial $10; the only exception is when replacing a Clean Vehicle Pass.

    Does this program last forever?

    No. The section of federal code allowing for the creation of the Clean Vehicle Program for the Express Lanes expires on September 30th, 2025.

Carpooling in the Express Lanes

    What qualifies as a carpool?

    You must have a total of 2 or more people in your vehicle to qualify as a carpool. An Express Pass is not required to access the Express Lanes when carpooling.

    Will I be charged when I'm carpooling if I have an Express Pass in my vehicle?

    To receive the 100% toll discount when carpooling, your Express Pass must be switched to the “HOV” setting.

Laws and Regulations

    What is the penalty for violating the Express Lanes' carpool requirement?

    Driving alone in the Express Lanes without an Express Pass in TOLL mode may result in a fine of $337 or more.

Contact Information

    General Information

    Phone: 801-887-3790
      Email: expresslanes@utah.gov
        Mailing address:
        • UDOT Express Lanes
        • PO Box 148270
        • Salt Lake City, Utah 84114