AB Bus Schedule: Routes, Times & Stops
Looking for the AB bus schedule? The main U.S. service covered by this guide is RTD’s AB airport bus family connecting Boulder, U.S. 36 stations and Denver International Airport (DEN). The official combined timetable includes AB1, AB2 and AB3 service patterns.
Find selected departure times, branch differences, fares, major stops, airport boarding information, current construction changes and the official live tracker. This guide also explains how to choose the right AB bus without confusing one Boulder branch with another.
Where Can You Find the Current AB Bus Schedule?
Open the official RTD combined AB timetable. Choose eastbound for travel toward DEN or westbound for travel toward Boulder, select your day of service and compare AB1, AB2 and AB3 timepoints. Use the live map and alerts for your exact stop before leaving.
AB Bus Schedule Guide
AB1 vs AB2 vs AB3: Which Airport Bus Should You Take?
RTD uses the AB route family for airport connections from Boulder. The U.S. 36 portion is shared by many trips, but Boulder stop patterns vary. Select the branch that serves your actual boarding point.
AB1 — Broadway
Connects Downtown Boulder and the Broadway corridor with Table Mesa and DEN. Important stops include Broadway/Euclid near CU Boulder and Broadway/27th Way.
For a branch-specific explanation, see our AB1 Boulder–Denver Airport timetable and stop guide.
Official AB1 TimesAB2 — 28th Street
Uses the Boulder Junction / 28th Street pattern, serving locations such as Boulder Junction at Depot Square, 28th/Canyon, 28th/Arapahoe and Table Mesa before the airport portion.
Use AB2 when the scheduled trip serves your 28th Street stop. It does not automatically serve every AB1 Broadway stop.
Official AB2 TimesAB3 — Canyon / 28th
RTD identifies AB3 trips through the Canyon and 28th Street area, with Boulder stops that can include Downtown Boulder, McGuckin, 28th/Arapahoe and Table Mesa.
Not every AB3 trip has the same daily availability. Verify the exact date, direction and stop using RTD.
Official AB3 TimesVisual Guide to the AB Branches
AB Bus Schedule: Selected Weekday Boulder to DEN Times
RTD’s combined schedule lists airport-bound timepoints for the different AB patterns. The examples below are selected Monday–Friday eastbound trips displayed in the official RTD timetable during this review. They are not the full timetable, and RTD labels scheduled times as approximate.
| Branch / Origin | Origin departure | Table Mesa | DEN arrival | Ride time from origin |
|---|---|---|---|---|
| AB1 Downtown Boulder | 2:57 AM | 3:20 AM | 4:10 AM | 73 min |
| AB1 Downtown Boulder | 4:27 AM | 4:50 AM | 5:40 AM | 73 min |
| AB via 28th St Boulder Junction | 5:44 AM | 6:05 AM | 6:55 AM | 71 min |
| AB via 28th St Boulder Junction | 7:42 AM | 8:05 AM | 9:01 AM | 79 min |
| AB1 Downtown Boulder | 9:37 AM | 10:05 AM | 11:01 AM | 84 min |
| AB via 28th St Boulder Junction | 5:11 PM | 5:35 PM | 6:31 PM | 80 min |
| AB1 Downtown Boulder | 10:09 PM | 10:35 PM | 11:27 PM | 78 min |
One Early AB1 Trip: Stop-by-Stop Timepoints
| Location | Scheduled time | Why it matters |
|---|---|---|
| Downtown Boulder Station | 2:57 AM | Starting terminal for this trip |
| Broadway / Euclid — CU | 3:06 AM | University-area boarding |
| Broadway / 27th Way | 3:09 AM | Central Boulder timepoint |
| US 36 & Table Mesa | 3:20 AM | Major airport-bus connection; temporary boarding rules apply |
| US 36 & McCaslin | 3:26 AM | Superior / Louisville connection |
| US 36 & Flatiron | 3:33 AM departure | Broomfield-area station |
| Denver Airport Station | 4:10 AM | DEN Transit Center, not the airline gate |
For additional help interpreting timepoints, dashes, arrival estimates and stop-specific departures, our guide to reading transit bus schedules explains the difference between planned departure times and live predictions.
How Long Does the AB Bus Take?
Full Boulder-to-DEN trips in the examples above take approximately 70–85 minutes, depending on origin, branch and departure period. These are selected scheduled journey times, not guaranteed travel times.
Illustrative bar scale: 100% = 100 minutes. Values reflect selected timetable examples, not real-time measurements.
AB Bus Weekend and Holiday Schedule
AB service is not represented by one identical Monday-through-Sunday timetable. RTD publishes separate weekday, Saturday and Sunday/Holiday schedule selections. The available AB branches and stop patterns can also differ.
RTD Holidays With Sunday/Holiday Service
RTD lists New Year’s Day, Memorial Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day as holidays using its Sunday/Holiday schedule. Extra special-event or service notices may still apply.
Major AB Bus Stops Between Boulder and DEN
The official AB schedule includes multiple Boulder origins and shared U.S. 36 stations. The list below is a practical route overview, not every stop or a guarantee that all three branches stop at each point.
| Stop / station | Main relevance | Branch note |
|---|---|---|
| Downtown Boulder Station | Boulder transit hub near 14th/Walnut | AB1 and selected other patterns; verify trip |
| Broadway / Euclid | University of Colorado area | AB1 Broadway pattern |
| Broadway / 27th Way | Boulder timepoint | AB1 Broadway pattern |
| Boulder Junction at Depot Square | Boulder Junction transfer facility | AB2 / 28th Street pattern |
| 28th / Canyon and Arapahoe | 28th Street corridor | Selected AB2 / AB3 patterns |
| US 36 & Table Mesa | Major Park-n-Ride and shared AB connection | Temporary gates and boarding locations |
| US 36 & McCaslin | Louisville / Superior area | Check gate and elevator status |
| US 36 & Flatiron | Broomfield-area station | Shared airport corridor timepoint |
| Denver Airport Station | DEN Transit Center, airport and A Line connection | Verify current boarding gate |
AB Bus Ticket Price, Airport Fare and How to Pay
Trips starting or ending at Denver International Airport normally require RTD’s airport fare product. The standard Airport Day Pass is $10. Other RTD fares can apply to eligible discounted travelers or partial AB trips that do not reach the airport.
Valid for the service day across RTD, including travel to or from Denver International Airport.
Confirm current fare conditions before boarding.Other RTD Fares
These non-airport products have different conditions. RTD states that eligible discount fares include airport travel.
How to Pay on the AB Bus
If you are connecting to buses or rail outside the airport corridor, see our RTD Denver routes, fares and transfer guide for the wider regional network and alternative services.
Verify Official RTD FaresAB Bus Stop Changes and Alerts: October 2026
RTD’s airport route pages list service adjustments and construction-related notices. These were reviewed on October 9, 2026; check RTD again on your travel day because alerts can change or expire.
RTD began structural repair work at Table Mesa on March 23, 2026. Gates B and C in front of the parking garage are temporarily closed.
- Arriving AB/FF passengers: buses use the stop along Table Mesa Drive across from the Park-n-Ride for deboarding.
- Eastbound airport-bound boarding: use the south-ramp boarding plaza on the south side of U.S. 36, accessed via Level 4 of the garage and pedestrian bridge as directed by RTD.
- Westbound boarding: use Gate E along Table Mesa Drive.
RTD estimates the construction period may extend into September 2027. Follow temporary signs and accessibility instructions at the station.
RTD adjusted the AB1 and AB2 schedule relationship at Table Mesa toward a consistent combined 30-minute pattern. The published notice describes arriving trips aligned at :00 and :30 with departures five minutes later.
This does not mean every Boulder boarding stop receives a bus every 30 minutes. It relates to the combined Table Mesa airport corridor pattern.
RTD lists a temporary closure affecting eastbound stop #35482 at the 13600 block of Via Varra. The listed alternate is US 36 & Flatiron Station Gate A, stop #34657. The notice identifies AB1, AB2 and AB3 among affected routes.
Reconfirm the closure and alternative stop before your trip.
RTD also lists an east-side elevator access issue at US 36 & McCaslin Station, with bus shuttles replacing bridge access. Construction notices also affect Broadway/Table Mesa stops during an October–December period. Accessible boarding details should be checked directly with RTD.
Where Does the AB Bus Stop at Denver International Airport?
The AB bus serves Denver Airport Station at the DEN Transit Center. The Transit Center is connected to Jeppesen Terminal, where passengers continue to airline check-in, baggage services and security.
Arriving at DEN
- Exit the AB bus at Denver Airport Station.
- Follow signs toward Jeppesen Terminal.
- Use the airport’s elevators, escalators or accessible route.
- Continue to airline check-in and security.
Leaving DEN for Boulder
- Follow signs to the DEN Transit Center.
- Check RTD’s current westbound AB departure.
- Confirm the boarding gate and bus headsign.
- Board the correct AB branch for your Boulder destination.
Denver Airport Station and AB Bus Location Map
The map shows the Denver Airport Station area. It helps orient riders at DEN; it is not a complete AB route map or a substitute for the official RTD stop list.
- Confirm Denver Airport Station.
- Find the current AB boarding gate.
- Check eastbound or westbound direction.
- Check the Table Mesa boarding changes if transferring.
For journeys from hotels, homes or other starting addresses, our Google Maps transit directions tutorial explains how to choose an arrival deadline, compare connections and inspect the actual walking route to the bus stop.
How Early Should You Catch the AB Bus for a Flight?
The bus arrival at Denver Airport Station is not the same as reaching your airline gate. You still need time to walk into the terminal, check luggage if necessary, pass through security and reach the departure gate.
Consider an earlier departure if you have checked luggage, require accessible assistance, are unfamiliar with DEN, or are traveling during winter weather.
How to Track the AB Bus in Real Time
RTD Next Ride provides schedule and live vehicle information where reporting is available. A predicted arrival may change because of traffic, weather, a detour, operator availability or a vehicle-location problem.
Wheelchair Access, Luggage and Boarding Tips
Before Boarding an AB Bus
- Check the full AB branch and headsign.
- Reach the station 10–15 minutes before your planned trip when practical.
- Use the correct gate for your direction.
- Have your fare or payment method ready.
- Keep luggage and mobility equipment clear of the doors.
- Confirm the last return trip from DEN.
- Review same-day detours and weather warnings.
- Allow extra connection time when boarding from a Park-n-Ride.
What If the AB Bus Is Late or You Miss It?
RTD Customer Service and Airport Assistance
Route times, stop information, trip planning and fare questions.
RTD security assistance. Call 911 for an emergency.
DEN station access and public transit information.
When asking RTD for assistance, provide the AB branch, direction, stop number, location, date, planned departure time and current alert if known.
Official Sources Used for This AB Bus Guide
Schedules and service alerts change. These official sources control the operational details. Use them to confirm same-day service, fares, boarding locations and departure predictions.
Review date: October 9, 2026. Selected times are scheduled examples; fare and alert data are subject to subsequent RTD changes.
AB Bus Schedule FAQs
What is the AB bus schedule?
RTD’s AB timetable covers airport bus service between Boulder and Denver International Airport. The combined schedule includes AB1, AB2 and AB3 patterns, which differ in their Boulder stops and departure times.
Where can I find the current AB bus times?
Use RTD’s official combined AB schedule and select the travel day and direction. For a particular boarding point, use the branch-specific timetable and live stop prediction.
What is the difference between AB1, AB2 and AB3?
AB1 serves the Broadway corridor, AB2 serves a Boulder Junction and 28th Street pattern, and AB3 serves a Canyon/28th-area pattern. Exact stop sequences and operating trips vary.
How much is the AB bus to Denver Airport?
RTD’s standard Airport Day Pass costs $10. Eligible discount fares and passes have different rules, and RTD states that qualifying discount fares include airport travel.
How long does the AB bus take from Boulder to DEN?
Selected full-route timetable examples take approximately 70–85 minutes, depending on the Boulder origin and departure. Actual travel can be longer because of traffic, weather and disruptions.
Does the AB bus stop at Table Mesa?
The shared airport corridor includes US 36 & Table Mesa Station, but ongoing construction has temporarily relocated boarding and deboarding locations. Check RTD’s active instructions before waiting at the station.
Does the AB bus run on weekends?
RTD publishes Saturday and Sunday/Holiday AB schedule selections. Branch availability and departure times can differ from weekdays, so check the current date-specific timetable.
Where do I catch the AB bus at Denver Airport?
AB buses use Denver Airport Station at the DEN Transit Center. Confirm the correct westbound gate in the current RTD schedule and follow the airport’s posted transit signs.
Can I pay cash for the AB bus?
RTD accepts cash payment on buses, but drivers do not make change. RTD also provides eligible Tap-n-Ride and MyRide payment options.
How do I track the AB bus live?
Use RTD Next Ride, choose the combined AB route or the exact branch, select direction and stop, and compare the predicted arrival with the current timetable and active alerts.