Half Marathon5KRegistration open

Cambridge Half Marathon + 5K

Oct 31 – Nov 1, 2026Cambridge, Massachusetts401 spots

Entry from: $45
Days to go: 25

At a glance

Date: Oct 31 – Nov 1, 2026
Location: Cambridge, Massachusetts
Distances: Half Marathon, 5K
Registration: Registration open until Nov 1, 2026, via runsignup.com
Official site: runsignup.com
Listed from: RunSignUp
Last checked: Oct 5, 2026

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About this race

The Cambridge 5K is the kickoff to race weekend! It's a 3.1-mile course that starts and finishes at CambridgeSide. It's a quick out and back along the Charles River that will have you in awe of the Boston skyline.

The Cambridge Half Marathon is a 13.1-mile USATF certified course that starts and finishes at CambridgeSide. It is a fast and flat course along Memorial Drive featuring views of the Charles River, MIT, John W. Weeks Footbridge, Harvard University Stadium, and more.

Key dates

Registration opens

Dec 30, 2025

Tier 1 ends

Dec 31, 2025

Tier 2 ends

Apr 10, 2026

Tier 3 ends

Jun 29, 2026

Tier 4 ends

Aug 14, 2026

Tier 2 ends

Oct 25, 2026

19d

Race day

Oct 31, 2026

25d

Tier 5 ends

Oct 31, 2026

25d

Tier 3 ends

Oct 31, 2026

25d

Registration closes

Nov 1, 2026

26d

Tier 5 ends

Nov 1, 2026

26d

Pricing

Cambridge Half Marathon + 5K Challenge

Tier 5, until Oct 31, 2026

$210

Cambridge Half Marathon + 5K Challenge Charity Runner

Tier 5, until Oct 31, 2026

$210

Cambridge Half Marathon

Tier 5, until Nov 1, 2026

$135

Cambridge Half Marathon Charity Runner

Tier 5, until Nov 1, 2026

$135

Cambridge 5K

Tier 2, then $50 from Oct 26, 2026

$45

Cambridge 5K Charity Runner

Tier 2, then $50 from Oct 26, 2026

$45

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Tune-up races

Boston 10K for Women
Oct 10Boston, MA10K
10K, 3 weeks before race day, 2 mi away, registration open
Downriver Rail Run
Oct 10Enfield, NH10K
10K, 3 weeks before race day, 103 mi away, registration open
Roxbury Road Race Series #30
Oct 10Roxbury, CT8.2 mi
8.2 mi, 3 weeks before race day, 126 mi away, registration open

Straight-line distance

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