Is August a good month for an Ultra?
It is one of the thinnest months of the year for the Ultra. August carries 8, against 37 in April. Expect to book earlier and travel further, and start from the states below rather than from a date.
Race calendar · August 2027
Ultramarathons in August 2027
8 ultramarathons across the US in August 2027, sorted by date. Which weekends are busiest, what the fields actually run, entry fees, and where each one starts.
August ultras in the United States are a study in extremes. The mountain West opens some of its most spectacular high-country windows this month, while the South, mid-Atlantic, and Midwest are still deep in summer heat and humidity. If you are planning one, know the region before you register.
August also sits at an awkward point in the training year. A runner peaking now likely started building in late spring, carrying fitness through the hottest weeks of summer. Heat adaptation can become a real asset on race day, but underestimating it in training is the most common way August ultras go wrong.
What the field actually runs
August Ultramarathons, By the Numbers
6:41:57Median finish time
4:09:55Median winning time
66Median field size
5August ultramarathons with published results
How we calculate these stats: RunSesh calculates these figures from the most recent published results of past editions, sourced from RunSignup. We show aggregates only: field size, winning and median times, and the cutoff. We never publish individual finisher tables. Last updated Nov 12, 2026.
When in August
The August Race Weekends
Ultramarathons are not spread evenly across August. Here is how the calendar actually falls, weekend by weekend, which is the part worth knowing before you book a trip or plan a taper around one.
By the numbers
The Biggest Field
The largest field of any August Ultra, from the most recent published results.
August Ultramarathons by State
Ultra Marathons by City in August
The Next Ultra Marathons in August
8 total Sat, Aug 7, 2027Sheep Mountain Trail Runs Fairplay, CORegistration opens Dec 1From $130Details Sat, Aug 7, 20273H Trail Half Marathon + DHRT 50K King George, VAFrom $105Details Sat, Aug 7, 2027Loopy Looper Pennsauken, NJRegistration opens Dec 12From $225Details Sat, Aug 14, 2027Eastern States 100 Waterville, PAFrom $295Details Sat, Aug 14, 2027Run S'more 24 Nashotah, WIFrom $85Details Sat, Aug 14, 2027Redwood (Summer) Trail Run Oakland, CAFrom $90Details Sun, Aug 22, 2027Anchorage RunFest Anchorage, AKRegistration opens Dec 1From $85Details Sat, Aug 28, 2027UltraTrax Wachusett Westminster, MAFrom $116Details
Common Questions About Running an August Ultra
How does August heat change the way you should pace and crew an ultra?
Start conservatively even when you feel good in the first hours. Aid station stops matter more than usual: swap fluids, address cooling, and do not skip a stop to make up time. In mountain races, afternoon thunderstorms can arrive quickly, so check your split schedule against typical storm windows for that area.
What should I wear and carry for an August ultra in the US?
Light, breathable fabric that handles sweat and dries fast is the core choice. A lightweight shell earns its place in mountain or high-elevation races where afternoon weather can turn fast. For lower-elevation or flat courses, prioritize sun protection: a brim, arm sleeves, and sunscreen reapplied at crew points.
Is August a good time to travel for an ultra, or should I race closer to home?
The mountain West races in August reward the trip: cooler high-altitude air, dramatic terrain, and courses that are genuinely hard to replicate closer to sea level. If you are traveling to a lower-elevation or humid-climate race, weigh whether the course justifies the added heat stress compared to waiting for a fall event.
How far ahead should I start training to be ready for an August ultra?
A full summer build starting in late April or May gives you enough time to develop the base, peak, and then taper without compressing any phase. Training through June and July also forces you into heat adaptation automatically, which is genuinely useful preparation for racing in August conditions.
When in August are most ultramarathons held?
The busiest weekend is August 7 and August 8, with 3 of them. Every one of them is on a Saturday or a Sunday.
What is a good Ultra time?
Across the 5 of these August ultramarathons with published results from past editions, the median finisher ran 6:41:57, and the median winning time was 4:09:55. So anything under 6:41:57 puts you in the faster half of a typical field. That is the middle of these RunSignup fields, walkers and charity entrants included, not a national average.
How big is a typical August Ultra field?
The median one finished 66 runners, across the 5 of these August ultramarathons with published results from past editions. Most are far smaller than the big-city events people picture, which means less crowding at the start and a friendlier field, with a last recorded finisher at 8:53:05.
Are there trail ultramarathons in August?
Yes, 4 races around the United States get you off the pavement: 4 are trail races.