I-405 Express Toll Lanes - Shoulder Lane Use for Authorized Buses


Bus shoulder lanes are authorized bus-only lanes running along the right shoulder of selected freeways. They are a low-cost solution that fully utilizes the capacity of existing corridors and provides immediate benefits to fixed route buses operated by local transit agencies.

Being on the right shoulder, buses entering the freeway from right-side on-ramps at SR 527 and SR 522 during peak morning congestion no longer have to weave through several lanes of traffic to access the left-side HOV lane.

The bus shoulder lanes are not designed to carry a large amount of traffic and are only used weekdays from 6 to 9 a.m. so buses can maintain a reliable schedule during periods of peak congestion.

Currently, there are bus shoulder lanes only along southbound I-405 in Bothell from SR 527 on-ramp to NE 195th Street off-ramp and from SR 522 on-ramp to NE 160th Street off-ramp.

Who can use bus shoulder lanes?
Only licensed professional bus drivers on fixed routes from the following agencies are allowed to use bus shoulder lanes at low speeds in order to bypass heavy traffic:

  • Community Transit
  • King County Metro Transit
  • Sound Transit

In addition, all drivers must be trained in the operating rules of bus shoulder lanes and able to handle complex driving decisions while in the shoulder. The large size of transit buses also makes it easier for those vehicles to be seen by other motorists and allows drivers to sit high enough to see potential hazards within the shoulder. Transit-operated paratransit and vanpools or HOV vehicles are not allowed in the bus shoulder lanes.

How do bus shoulder lanes operate?
Bus shoulder lanes look and operate like any other shoulder and have a minimal effect on traffic in the general purpose or HOV lanes. The shoulder will still be available first for disabled vehicles, incident response and emergency or enforcement situations. The lanes are designed for adequate stopping sight distance with the reduced operating speeds.

Buses using the southbound I-405 bus shoulder lanes cannot exceed all other traffic by more than 15 mph to ensure safe travel for all corridor users. The maximum speed allowed is 35 mph.

All bus drivers traveling in bus shoulder lanes will have to yield to all other traffic, including any vehicles entering the shoulder and all motorists in the general purpose or HOV lanes when exiting the shoulder.

Signs alerting non-transit drivers of the potential for buses traveling along the shoulder during designated hours are posted along freeway corridors with bus shoulder lanes. Supplemental "Emergency Stopping Only" signs are located throughout the corridor.