100K Races in the US
As of October 6, 2026, Crewable lists 131 upcoming 100K races in the US from October 2026 to September 2027. The next is HOKA Kodiak Ultra Marathons by UTMB on October 8 in Big Bear Lake, CA. Registration is open for 41. One advertises prize money.
Sources: UltraSignup, RunSignUp, UTMB, race organizers and race websites
With aid station data
9 aid
2 aid
9 aid
6 aidRace calendar
October 2026
28 racesThe Mammoth Trail Run 2026 - 100K / 50K / 25K / 10K / 5K and Mighty Mammoth 1K Kids Dash
Glen Rose, TX100K50K+3Open until Oct 11from $35
November 2026
19 racesDecember 2026
15 racesJanuary 2027
10 racesFebruary 2027
8 racesMarch 2027
6 racesApril 2027
14 racesMay 2027
7 racesJune 2027
12 racesJuly 2027
4 racesAugust 2027
4 racesSeptember 2027
4 races100K races by state
- Texas21
- California15
- Tennessee7
- Arizona6
- Florida6
- Virginia6
- Washington6
- Kansas4
- Louisiana4
- Missouri4
- North Carolina4
- New York4
- Pennsylvania4
- Utah4
- Alabama3
- Arkansas3
- Colorado3
- Illinois3
- Nevada3
- Ohio3
- Oklahoma3
- Connecticut2
- Iowa2
- Wisconsin2
- Georgia1
- Idaho1
- Indiana1
- Maine1
- Michigan1
- Minnesota1
- New Jersey1
- South Carolina1
- West Virginia1
Quick answers
What is the next 100K race in the US?
HOKA Kodiak Ultra Marathons by UTMB, on Thursday, October 8, 2026, in Big Bear Lake, CA. Distances: 100 mi, 100K, 50K.
How many 100K races in the US have open registration?
41 of the 131 list registration as open as of October 6, 2026, including Outback in the Ozarks 205 Mile Relay, Oil Creek 100 Trail Runs and The Mammoth Trail Run 2026 - 100K / 50K / 25K / 10K / 5K and Mighty Mammoth 1K Kids Dash.
Which 100K races in the US offer prize money?
One race advertises prize money.
Which states have the most 100K races?
Texas (21), California (15) and Tennessee (7).
What is the busiest month for 100K races in the US?
October 2026, with 28 of the 131. November 2026 follows with 19.
By month
More ways to browse
All states
- Alabama111
- Alaska5
- Arizona84
- Arkansas71
- California303
- Colorado98
- Connecticut88
- Delaware24
- District of Columbia4
- Florida296
- Georgia200
- Hawaii6
- Idaho24
- Illinois121
- Indiana96
- Iowa50
- Kansas58
- Kentucky71
- Louisiana73
- Maine39
- Maryland95
- Massachusetts89
- Michigan146
- Minnesota27
- Mississippi29
- Missouri104
- Montana21
- Nebraska21
- Nevada39
- New Hampshire26
- New Jersey160
- New Mexico31
- New York176
- North Carolina201
- North Dakota2
- Ohio179
- Oklahoma47
- Oregon65
- Pennsylvania194
- Rhode Island19
- South Carolina111
- South Dakota6
- Tennessee134
- Texas317
- Utah79
- Vermont25
- Virginia160
- Washington130
- West Virginia32
- Wisconsin87
- Wyoming9
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