5KRegistration open

Issaquah Schools Foundation Monster Mash 5K

Saturday, October 24, 2026Issaquah, Washington

Entry from: $40
Days to go: 18

At a glance

Date: Oct 24, 2026
Location: Issaquah, Washington
Distances: 5K
Registration: Registration open until Oct 23, 2026, via runsignup.com
Official site: isfdn.org
Listed from: RunSignUp
Last checked: Oct 5, 2026

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About this race

Help us raise a MONSTROUS amount of support for local students on October 24th! ISF Monster Mash 5K is a community-based, family-friendly event that raises funds for programs that serve students attending all 27 ISD schools.

We welcome all-ages and abilities. Convenient onsite parking, phased start times, and a professionally chip-timed course ensure a great experience for all. You’ll appreciate the flat, paved, out-and-back route whether you’re setting a new 5K PR or enjoying a brisk walk together as a family! Bring your creativity – festive costumes are encouraged!

This event sells out every year, so don't wait to register! Every registration submitted by October 12th receives a 2026 Monster Mash technical race tee & medal. Registrants receive free event photos and raffle tickets for prizes as well! Placement awards for fastest finishing times will also be presented. See below for details.

Key dates

Registration opens

Sep 8, 2026

Tier 1 ends

Sep 19, 2026

Tier 2 ends

Oct 12, 2026

Tier 3 ends

Oct 20, 2026

14d

Registration closes

Oct 23, 2026

17d

Tier 3 ends

Oct 23, 2026

17d

Race day

Oct 24, 2026

18d

Pricing

In-Person 5K

Tier 2, then $45 from Oct 12, 2026

$40

In-Person 5K (No T-Shirt)

Tier 2, then $45 from Oct 12, 2026

$40

Virtual 5K

Tier 2, then $45 from Oct 12, 2026

$40

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