Washington · Half Marathon · 10K · 5K
Mercer Island Half Marathon, 10K & 5K
Mercer Island Half Marathon, 10K & 5K is a half marathon, 10K and 5K event held in Mercer Island, Washington. Its next confirmed date is Friday, March 26, 2027. About 4,500 runners take part across all distances.
- Race day
- March 26, 2027
- Location
- Mercer Island, WA
- Field size
- ~4,500 runners
Race details
- Date
- Friday, March 26, 2027
- Location
- Mercer Island, Washington
- Distances
- Half Marathon, 10K, 5K
- Field size
- About 4,500 runners
- Course
- Rolling, moderately hilly half-marathon loop around Mercer Island (approx. 600-800 ft gain)
- Registration
- raceentry.com
- Official website
- mercerislandhalf.com
About the Mercer Island Half Marathon, 10K & 5K
A scenic, long-established springtime race circling Mercer Island that raises funds to fight colon cancer through the Rotary Club of Mercer Island Foundation.
Rankings and notes
- Rankings and awards
- One of the oldest and largest spring half marathons in the Seattle metro; long-running Rotary Club fundraiser
More half marathons in Washington
Coming up next, by confirmed date.
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Guides from the RaceRove blog
- 8 min read How to Choose the Best Half Marathon for a PR, Racecation or 50-State Challenge The best half marathon depends on what you want from it. How to choose a course for a personal record, a race worth travelling for, or an efficient stop on a 50-state challenge.
- 7 min read How to Find a 5K, 10K, Half Marathon or Marathon Near You A practical way to find running races near you: pick a distance, decide how far you'll travel, read the listing properly and confirm the details before you register.
- 9 min read How to Run a Race in All 50 States How to plan a 50-state running challenge: set your own rules, group states into trips, build a calendar around the seasons, budget for it and keep track of every finish.
- Blog All guides Planning advice for finding, choosing and travelling to races.
Mercer Island Half Marathon, 10K & 5K: common questions
- When is the Mercer Island Half Marathon, 10K & 5K?
- The next confirmed date is Friday, March 26, 2027.
- Where is the Mercer Island Half Marathon, 10K & 5K held?
- In Mercer Island, Washington.
- What distances does the Mercer Island Half Marathon, 10K & 5K offer?
- Half Marathon, 10K and 5K.
- How many people run the Mercer Island Half Marathon, 10K & 5K?
- About 4,500 runners across all of its distances. That figure is an estimate of the field size, not an entry cap.
- How do I register for the Mercer Island Half Marathon, 10K & 5K?
- Registration is handled by the organiser at raceentry.com. Entry fees, caps and deadlines are set there.
Plan this race in RaceRove
Save it to your plan, compare it with other races, check typical race-day weather and track your 50-state progress in the interactive app.