Race calendar · October 2026 · Idaho

October 2026 Half Marathon Races in Idaho

Every Half Marathon in Idaho in October 2026, all 8 of them, sorted by date. Dates, entry fees, finish-time stats from past results, and start-line maps.

8 Half Marathon races in October 2026

5K in October10K in OctoberMarathon in October

When in October

The October Race Weekends

Half Marathon races do not spread evenly across October. The busiest weekend is October 24 and October 25, with 4 of them.

  1. Oct 10 – Oct 113
  2. Oct 17 – Oct 181
  3. Oct 24 – Oct 254

By the numbers

The Biggest and Longest-Running

The October Half Marathon races that stand out on the numbers: the biggest field, and the longest unbroken run of editions.

Largest field715 finishersCity of Trees Marathonin the Half Marathon

October Half Marathon Races by City

Boise 3Cambridge 1Coeur D Alene 1Coeur d'Alene 1Hayden Lake 1Rexburg 1
Open map ↗

Soonest Half Marathon Races in October

8 total
Sat, Oct 10, 2026Hayden Lake Marathon Hayden Lake, IDMarathonHalf Marathon6.55 Miles5KFrom $55Details Sat, Oct 10, 2026Rush Creek Stampede Cambridge, IDHalf Marathon5K10KFrom $40Details Sun, Oct 11, 2026City of Trees Marathon Boise, IDMarathonHalf Marathon10K5KFrom $20Details Sat, Oct 17, 2026Idaho Running Day Boise, IDMarathonHalf Marathon10K5KFrom $50Details Sat, Oct 24, 2026YMCA Halloween Run Boise, IDHalf Marathon5K1 MileFrom $30Details Sat, Oct 24, 2026Haunted Half Marathon and 5k by Run the Undergrad Rexburg, ID5KHalf MarathonFrom $10Details Sat, Oct 24, 2026Eternal Surrender Half Marathon Coeur D Alene, IDHalf MarathonFrom $35Details Sun, Oct 25, 2026Halloween Hustle Coeur d'Alene, IDHalf Marathon10K5K0.5 MilesFrom $30Details

Common Questions About Running an October Half Marathon in Idaho

When in October are most Half Marathon races held?

The busiest weekend in Idaho is October 24 and October 25, with 4 Half Marathon races on those two days, and the single busiest day is Saturday, October 24 with 3. Every one of them is on a Saturday or a Sunday.

When should I sign up for an October Half Marathon?

As early as you can. 2 of these October Half Marathon races already have a price increase on the calendar, and 8 are open for entry right now.

How much does an October Half Marathon cost to enter?

The typical entry is $35, with paid entries running from $10 up to $55. Entry fees climb as race day gets closer, so the same race is usually cheapest the week it opens.

Half Marathon Races in Other Months

September and November sit either side of October, which is where most people look next when a date does not fit.

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