See all October 2023 half marathons across the USA below, or click Race Calendars above to see each state’s calendar. For each race, you’ll find course maps, elevation profiles, reviews and info on how to register.
Sunday, October 1
| Sun Oct 1 | Ann Arbor Marathon Half Marathon 10K & 5K | Ann Arbor MI |
| Sun Oct 1 | Greenway Marathon & Half Marathon | Nashville TN |
| Sun Oct 1 | Maine Marathon Half Marathon & Relay | Portland ME |
| Sun Oct 1 | Peace Officer Memorial Run Half Marathon 5k 1M & Relay | Modesto CA |
| Sun Oct 1 | Portland Marathon & Half Marathon | Portland OR |
| Sun Oct 1 | Rails to Trails Marathon Half Marathon 5k & 1M | Norwalk WI |
| Sun Oct 1 | Rock 'n' Roll San Jose Half Marathon & 10K | San Jose CA |
| Sun Oct 1 | Rockfest Half Marathon | Hampton Beach NH |
| Sun Oct 1 | Urban Cow Half Marathon | Sacramento CA |
| Sun Oct 1 | Wineglass Marathon & Half Marathon | Corning NY |
Monday, October 2 – Friday, October 6
| Mon Oct 2 | Center of the Nation Series – Day 1 Marathon & Half Marathon | Sterling CO |
| Tue Oct 3 | Center of the Nation Series – Day 2 Marathon & Half Marathon | Chadron NE |
| Wed Oct 4 | Center of the Nation Series – Day 3 Marathon & Half Marathon | Sundance WY |
| Thu Oct 5 | Center of the Nation Series – Day 4 Marathon & Half Marathon | Belle Fourche SD |
| Fri Oct 6 | Center of the Nation Series – Day 5 Marathon & Half Marathon | Bowman ND |
Saturday, October 7
| Sat Oct 7 | Arches Marathon Half Marathon & 15K | Moab UT |
| Sat Oct 7 | Bemidji Blue Ox Marathon & Half Marathon Weekend | Bemidji MN |
| Sat Oct 7 | Cape Cod Marathon Weekend Half Marathon & 5K | Falmouth MA |
| Sat Oct 7 | Center of the Nation Series – Day 6 Marathon & Half Marathon | Baker MT |
| Sat Oct 7 | Indy Half Marathon at Fort Ben | Indianapolis IN |
| Sat Oct 7 | Key West Run Conch Republic Half Marathon & 10k | Key West FL |
| Sat Oct 7 | Lake Placid Classic Half Marathon & 10k | Lake Placid NY |
| Sat Oct 7 | Monkey Marathon & Half Marathon | Maineville OH |
| Sat Oct 7 | OmaHalf 10M & 5k | Omaha NE |
| Sat Oct 7 | Potomac River Run Marathon & Half Marathon | Washington DC |
| Sat Oct 7 | Rancho Canada del Oro Trail Challenge 30k Half Marathon 8M 10k & 5k | Morgan Hill CA |
| Sat Oct 7 | Reuel Little Classic Half Marathon 10k & 5k | Madill OK |
| Sat Oct 7 | St. George Marathon & Half Marathon | St. George UT |
| Sat Oct 7 | Under the Oaks Half Marathon & 10K | Jekyll Island GA |
| Sat Oct 7 | Whiskey Row Marathon Half Marathon 10k & 5k | Prescott AZ |
Sunday, October 8
| Sun Oct 8 | Boulderthon: Downtown Boulder Marathon & Half Marathon | Boulder CO |
| Sun Oct 8 | Girlfriends Run for a Cure Half Marathon | Vancouver WA |
| Sun Oct 8 | Greenbrier River Trail Marathon & Half Marathon | Cass WV |
| Sun Oct 8 | Humboldt Redwoods Marathon Half Marathon & 5K | Weott CA |
| Sun Oct 8 | Nantucket Half Marathon | Nantucket MA |
| Sun Oct 8 | Newport Marathon & Half Marathon | Newport RI |
| Sun Oct 8 | Paine to Pain Trail Half Marathon | New Rochelle NY |
| Sun Oct 8 | Rock n Roll Clearwater Half Marathon | Clearwater FL |
Monday, October 9-Friday, October 13
| Fri Oct 13 | Lake Tahoe Marathon & Half Marathon Weekend | South Lake Tahoe CA |
Saturday, October 14
| Sat Oct 14 | Arkansas Marathon Half Marathon 10k & 5k | Booneville AR |
| Sat Oct 14 | Country Sole Half Marathon | Chicago IL |
| Sat Oct 14 | Dimple Dell Half Marathon | Sandy UT |
| Sat Oct 14 | Escalante Canyons Marathon Half Marathon & 5k | Escalante UT |
| Sat Oct 14 | Lake Tahoe Marathon & Half Marathon Weekend | South Lake Tahoe CA |
| Sat Oct 14 | Mt. Umunhum Trail Conquest 50k Marathon Half Marathon & 5k | San Jose CA |
| Sat Oct 14 | Paris Mountain Half Marathon | Greenville SC |
| Sat Oct 14 | Queen Bee Half Marathon | Cincinnati OH |
| Sat Oct 14 | Run the Rails Half Marathon 10k 5k & 1M | Union City TN |
| Sat Oct 14 | Sauk Valley Apple Cider Run Half Marathon 10k & 5k | Rock Falls IL |
| Sat Oct 14 | Scenic Byway Half Marathon & 5K | Belle Plaine MN |
| Sat Oct 14 | Twilight Red Rock Half Marathon 10K & 5K | Las Vegas NV |
| Sat Oct 14 | Urban Bourbon Half Marathon | Louisville KY |
Sunday, October 15
| Sun Oct 15 | Seven Bridges Marathon Half Marathon & 5K | Chattanooga TN |
| Sun Oct 15 | Baystate Marathon & Half Marathon | Lowell MA |
| Sun Oct 15 | City of Trees Marathon Half Marathon 10k & 5k | Boise ID |
| Sun Oct 15 | Happy Valley Half Marathon | Northampton MA |
| Sun Oct 15 | Lake Tahoe Marathon & Half Marathon Weekend | South Lake Tahoe CA |
| Sun Oct 15 | Long Beach Marathon & Half Marathon | Long BeachCA |
| Sun Oct 15 | Luray Half Marathon & 5k | Luray VA |
| Sun Oct 15 | Rogue Gorge Half Marathon | Union Creek OR |
| Sun Oct 15 | Sugar Land Half Marathon 10k & 1M | Sugar Land TX |
Saturday, October 21
| Sat Oct 21 | Harriman Big Bear Squatch Half Marathon | Tuxedo NY |
| Sat Oct 21 | Indiana Women's Half Marathon & 5k | Carmel IN |
| Sat Oct 21 | Kansas City Marathon Half Marathon 10K & 5K | Kansas City MO |
| Sat Oct 21 | Mankato Marathon Half Marathon & 10K | Mankato MN |
| Sat Oct 21 | Sandi McCool Champions of Hope Marathon 10k 5k & 1M | Dothan AL |
Sunday, October 22
| Sun Oct 22 | Columbia Gorge Marathon & Half Marathon | Hood River OR |
Saturday, October 28
| Sat Oct 28 | Canyonlands Ultra & Half Marathon | Moab UT |
