FAQs

General Information

The system monitors the freeway and raises or lowers the toll to keep traffic flowing smoothly in the express lanes. San Mateo 101 Express Lanes use “dynamic pricing” to set the toll price. Dynamic pricing is when the price to use the lane goes up or down depending on how crowded the lane is. Overhead message signs tell drivers the price to travel to a destination in the Express Lane. Tolls are paid using FasTrak®.

All vehicles need FasTrak® or FasTrak Flex® toll tags to use the lanes.

  • 3+ person carpools, vanpools, buses, and motorcycles can use the lane for free with a properly set FasTrak Flex or FasTrak CAV toll tag.
  • 2-person carpools can receive a 50% toll discount when using a properly set FasTrak Flex or FasTrak CAV toll tag.
  • Solo Clean Air Vehicle (CAV) drivers can receive a 50% toll discount with the FasTrak CAV toll tag.
  • Solo drivers will pay full tolls with FasTrak® or FasTrak Flex®.

Before starting your trip, solo drivers must set their FasTrak Flex toll tag to the “1” position so the toll system can charge the vehicle the proper toll. Carpools with two occupants would send the toll tag to the “2” position to get a toll discount. Carpools with three or more occupants or motorcyclists must set their toll tag to the “3+” position. The “2” and “3+” settings allow eligible vehicles to use the lanes toll free or for discounted tolls. These toll tag settings also trigger beacons that CHP officers use to enforce vehicle occupancy requirements.

Cars with a valid Clean Air Vehicle decal wishing to get a toll discount will need to use a FasTrak CAV toll tag. To apply for a FasTrak CAV toll tag, visit BayAreaFasTrak.org/cleanair.

Visit GetFasTrak.com for more information about FasTrak® and how to open an account.

No. Drivers only need one toll tag in the vehicle. Standard FasTrak® toll tags should be exchanged for a FasTrak Flex® toll tag. If multiple toll tags are in a vehicle, the toll system may detect the additional toll tag(s) and the trip may result in multiple toll charges.  More information about getting a FasTrak Flex® toll tag can be found here.

You can enter or exit the US 101 Express Lanes in San Mateo County at any point.

Two-person carpools in two-seater vehicles can travel toll-free in the US 101 Express Lanes in San Mateo County. Please set your FasTrak Flex transponder in the “3+” position before driving.

The San Mateo County Express Lanes is developing a program that will help qualifying San Mateo County residents cover some of their transportation costs, called the Community Transportation Benefits Program. For more details, go to the Community Transportation Benefits page or keep scrolling for more FAQs.

US 101 Express Lanes in San Mateo County operate Monday – Friday 5am-8pm. Outside of these hours, the lanes are open to all drivers at no charge.

All vehicles need FasTrak® or FasTrak Flex® to pay the toll using their FasTrak® account. If a vehicle enters the Express Lane without a FasTrak®, FasTrak Flex®, or FasTrak® account, a violation notice will be sent to the address where the vehicle is registered. This violation notice includes the value of the toll, plus a $10 penalty, which must be paid by the notice due date. If payment is not received within this period, a second notice will be sent, which includes the value of the toll, $10 penalty, and $20 late fee. Failure to pay the second notice may result in additional fees and withholding of your vehicle registration by the DMV and/or a referral to a collections agency.

The penalty is waived for first-time violators if you sign up for FasTrak®.

A Bay Area Toll Payment Plan exists for qualifying individuals whom have accumulated multiple toll violations. To find out if you are eligible or to apply for the payment plan, please click here.

Customers with a current California Department of Motor Vehicle (DMV) registered Clean Air Vehicle (CAV) can request a CAV FasTrak Flex® toll tag to use the Express Lane and receive the CAV discount.  For more information or to apply for a CAV FasTrak® toll tag, please visit www.BayAreaFasTrak.org/cleanair.  

For buses, including commuter shuttles, to use the San Mateo 101 Express Lanes for free, they must have a properly mounted FasTrak Flex® set to 3+. Buses and shuttles may also use the lanes for deadhead time.

For questions on FasTrak, call FasTrak’s Customer Service Center at 877-BAY-TOLL (877-229-8655), or visit GetFasTrak.com for more information about FasTrak® and how to open an account.

All lanes on the freeway are wide enough to accommodate all vehicles. After a thorough safety review, Caltrans engineers have determined that the Express Lanes meet Caltrans safety and operating standards. In many places along the corridor, the outside lanes are wider than the inner lanes.

When there is an accident in the Express Lanes, California Highway Patrol (CHP) will be notified and called to the location of the accident. During the accident, CHP has complete control over the toll system. The lane will be opened or closed to various vehicles at CHP’s discretion depending on the circumstances of the accident. The overhead signs will be updated with the status of the lane open or closure. In addition, CHP can close the Express Lanes if necessary to respond to an accident in the other General Purpose lanes or any other highway emergency.

Caltrans continues to provide lane sweeping to keep them clear of debris.

Carpool lanes, commonly referred to as “diamond lanes” or “high-occupancy vehicle (HOV) lanes,” are special lanes reserved for carpools, buses, motorcycles, or eligible clean air vehicles with decals to use during specific hours. Carpool lane hours of operation and carpool occupancy requirements vary by corridor and are posted on the roadside where restrictions apply. Carpool lanes are indicated with roadside signs that include the diamond symbol and the rules for use of the lane, as well as diamond markings on the pavement of the lane.

Express Lanes allow any vehicle, regardless of occupancy, to use the lane during operating hours for the posted price or at a discounted rate when meeting specific occupancy requirements. This allows solo drivers with a FasTrak® account to use the lane for a toll compared to a carpool/diamond lane in which a vehicle must meet the minimum occupancy to use the lane without being in violation of the California Vehicle Code Section 21655.5. Express Lanes in the Bay Area are indicated with roadside and overhead signs which display the FasTrak® requirement and other use rules, and are accompanied by "EXPRS LANE" markings on the pavement of the lane.

The SM101 Express Lanes price specific zones of the corridor between the various US-101 exits in San Mateo County. Prices to use the lane within these specific zones are posted on the overhead signs preceding the zones.  The limits of the pricing zones are the destinations noted on the overhead signs. Prices vary in each of the zones and accumulate if a vehicle drives through multiple zones based on what is displayed on the signs. The price a driver will be charged is the price that is displayed when they enter the lane, even if the price to that destination increases while they’re in the Express Lane. 

Tolling Zones

The graphic above is a basic depiction of signage on a portion of the northbound (NB) SM101 Express Lanes.  The following examples describe various trip scenarios and how a solo driver paying full price of posted tolls would be charged. In all scenarios, if the vehicle was a carpool of 3 or more passengers, then the trip would be toll-free and if the vehicle had 2 passengers or had a FasTrak Flex ® CAV tag, then the trip would be discounted.

Example 1: Driver A enters the NB Express Lane near Hillsdale Blvd in San Mateo when the sign reads as shown above.  Driver A exits the Express Lane to take the SR-92 exit from US-101.  Since Driver A only drove within zone 1 of the Express Lane, they are assessed the posted toll at the time the driver entered the Express Lane of $1.50.

Example 2: Driver B enters the NB Express Lane near Hillsdale Blvd in San Mateo when the sign reads as shown above.  This sign shows that it the full toll price of the first zone to SR-92 is $1.50 and through two zones—past SR-92 to the Broadway exit—would be $3.50. Driver B’s destination is on Broadway, so they continue in the Express Lane and then take the Broadway exit from US-101.  In this case, Driver B is assessed a toll of $3.50.

Example 3: Driver C sees the toll sign near Hillsdale Blvd and decides that they do not want to pay $3.50 to reach Broadway and remain in the General Purpose lane.  However, as they continue driving on US-101, they realize that they are running late to a doctor’s appointment, and Driver C decides to enter the Express Lane just past the SR-92 interchange (in zone 2).  Entry into the Express Lane allows Driver C to bypass some of the traffic, saving time, and they exit the Express Lane further downstream to take the Broadway exit from US-101.  In this case, Driver C only drove in zone 2, so Driver C is assessed a toll of $2.00.

Example 4: Driver D merges onto US-101 from SR-92 and safely enters the Express Lane just past the SR-92 interchange when the sign reads as shown above. Driver D remains in the Express Lane until exiting just past SFO to take the I-380 exit from US-101.  In this case, Driver D drove within zones 2 and 3 and is assessed a toll of $3.00.

Example 5: Driver E lives in Foster City and works in downtown South San Francisco but is running late leaving home.  Driver E enters US-101 at Hillsdale Blvd and immediately merges into the Express Lane to improve their travel time.  Driver E continues in the Express Lane until they reach their exit at E. Grand Ave in South San Francisco.  In this case, Driver E drove through all three zones and is assessed a toll of $4.50.

Additional information on how Express Lanes work can be found at the following links:

Community Transportation Benefits Program

The Program helps qualifying San Mateo County residents cover some of their transportation costs by offering the option of two different transportation benefits to qualified individuals: 1) A Clipper Card with a value of $100 provided annually, or 2) FasTrak® toll tag/transponder with value of $100 provided one time. Aside from these monetary benefits, the Express Lanes will reduce congestion in the 101 Corridor and improve travel times and reliability for bus riders and other Express Lanes users. For more details, go to the Community Transportation Benefits page.

No, this benefit is provided at the individual level. Multiple people who live within one household may receive this benefit if they meet the eligibility requirements.

If eligible, you can only select one of the transportation benefit options available.

Eligibility is verified through paystubs, a letter from your employer, or a benefits letter. If none of these options are available to you, you may sign a Self-Declaration statement stating your income.

The FasTrak® toll transponder allows you to use the express lanes or toll bridges free or at a discounted rate if you meet vehicle occupancy requirements even after the preloaded $100 is spent. The Core Services Agency case manager will assist you with the online FasTrak® registration process at the time of your enrollment. You do not need a credit card in order to register your FasTrak® toll transponder. For more information about FasTrak® discounts visit: https://511.org/driving/express-lanes

You are still eligible! You may register the new transponder you receive through the Community Transportation Benefits Program to your existing FasTrak® account. Ask a case manager for assistance.

No, you do not need to register your Clipper Card to spend the preloaded $100. However, it is highly encouraged that you do register your Clipper Card for renewal of your benefits annually. Plus, in case your Clipper Card is lost or stolen, your remaining benefits can be easily recovered.

Yes, Clipper START is a regional program that provides up to 50% in discounts on transit fare for qualified individuals. If you qualify for Clipper START you will receive a different Clipper Card associated with that discount program. For more information and to apply online, visit www.clipperstartcard.com/s/. Plus, most of the Core Service Agencies can provide brochures which contain paper applications and additional information about the Clipper START Program.

If you select the Clipper Card benefit, you may continue using the card, but will need to load additional funds to pay for future transit trips. Also, remember that the Clipper Card benefit is an annual benefit. For more information, please visit: www.ClipperCard.com.

If you select the FasTrak® toll transponder benefit, you can continue to use your transponder, however you will need to add funds to avoid toll penalties. You may add additional funds using cash or a credit card. For more information, please visit www.bayareafastrak.org.

The Community Transportation Benefits Program is sponsored and funded by the San Mateo US 101 Express Lanes.