How do I register for the Boulder Marathon?

Registration is open online on a first-come basis. The race sells out each year, so signing up early is strongly recommended. A limited number of charity bibs are also available through official charity partners if the main field is full.

Is the Boulder Marathon a Boston qualifier?

Yes, the course is USATF certified and qualifies for Boston. Keep in mind the race is run entirely above 5,000 feet, which affects pace for most runners, so the BQ rate is lower than at sea-level races.

What is the elevation profile like?

The course is a near-neutral net loop with roughly 836 feet of gain and a similar amount of loss spread across the 26.2 miles. The bigger factor for most runners is the altitude: you're running between 5,068 and 5,409 feet the entire race, which adds noticeable effort even on flat stretches.

What is the weather typically like on race day?

Late September brings cool mornings, often in the upper 40s at the gun, with afternoon highs that can reach the mid-70s. Runners finishing in the later hours should be ready to manage the heat and stay on top of hydration.

How big is the field?

The race draws close to 2,000 finishers, giving it the feel of a community event without the logistical scale of a large city marathon.

Is the course USATF certified?

Yes, the Boulder Marathon is USATF certified.

Sun, Sep 27 · 2026Boulder, COSince 2021

Boulder Marathon

The Boulder Marathon runs a loop through the heart of one of America's great running cities, starting and finishing near Pearl Street with the Flatirons as a backdrop. It's a genuine test at altitude, and it rewards runners who come prepared.

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BOULDER · US

Boulder

SUN, SEP 27

2026

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Race Overview

EST. 2021

Boulder is a running town, and this race feels like it. The course starts and finishes near Pearl Street, loops through the city and out into the surrounding roads, and brings you back with the Flatirons sitting right there the whole time. The rolling terrain is manageable, but the altitude is real. You're running above 5,000 feet for every mile. If you haven't spent time in Colorado before race day, give yourself at least a few days to adjust. Don't try to run your sea-level tempo effort in the first half. The course will let you, and you'll pay for it.

This is a Boston qualifier, but the altitude keeps the BQ rate modest, so it's not a guaranteed fast day. It suits runners who train in the mountains or who manage effort well. The field is a few thousand finishers, which gives the race a real community feel without being overwhelming. Registration is open and sells out each year, so sign up early once the window opens. If you miss the main bib, a limited number of charity spots come available through official partners. Come up a few days early, run easy on Pearl Street the day before, and give your lungs a chance to catch up.

Field size

~2k

1,998 finishers

BQ rate

3%

Below national average

Time limit

6:00

Tight cutoff

Entry

Open

First-come registration

Course records

Men

2:22:34

Ben Schneiderman

2023

Women

2:42:17

Hellen Jepkurgat

2023

The Course

836 ft total gain

Total ascent

↑836 ft

Total descent

↓824 ft

Net elevation

↑12 ft

Highest point

5,409 ft

Lowest point

5,068 ft

Course shape

Loop

Start and finish in one place

The course is a near-neutral net loop, but the 836 feet of gain means you'll earn the return. Elevation sits above 5,000 feet throughout, which adds roughly 5-10% perceived effort even for acclimatized runners. The course rolls through the early miles, so avoid banking time too aggressively before the halfway point. The back half mirrors the front in loss, giving you a chance to open up if you've been patient. Runners chasing a PR should treat the altitude as the primary variable: the legs may feel fine while the lungs quietly fall behind. Flat sections in the middle offer the best pacing windows.

DIFFICULTYHILLYPR-FRIENDLYNO

Past results

Race-Day Weather

10-year median

Low

47°F

High

76°F

30°MARATHON-IDEAL 45–60°80°

What to expect

Late September in Boulder means a wide spread between morning and afternoon. The gun goes off in cool conditions, and that part is fine. But by the back half of the race the temperature can climb into the mid-70s, especially if you're running a slower pace. Altitude makes warm air hit harder than it would at sea level. Dress in light layers you can shed early, and hydrate from the first aid station, not when you feel like you need it.

Entry

OPEN

Registration is open online; the race sells out each year so early sign-up is recommended. A limited number of charity bibs are also available through official charity partners.

Register on race site

Logistics

For runners travelling in

Closest airport

DEN

34 mi

from the start

≈ 54 min transferEasy transfer

What to expect

Fly into Denver International Airport (DIA), about 45 minutes from downtown Boulder by Uber, bus, or rental car. Hotels are available downtown Boulder near the Pearl Street Mall start and finish.

Frequently Asked

7 questions

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