Which Marathon Times Don't Count for Boston?

Published November 2, 2026 · Estimates, updated each registration cycle

Short answer: Boston only accepts a time from a full marathon run on a certified road course, in an official race with published results, inside the qualifying window. Treadmill marathons, virtual races, indoor marathons, time trials and handicapped races do not count, even if the time is real and well under your standard. Before you build a training block around a race, it is worth making sure the result you are chasing is one the B.A.A. will actually accept.

Treadmill marathons

A treadmill marathon is not a qualifier, whether you run it at home, in a gym or at a staged event. There is no certified course, no way to verify the distance independently, and belt speed and incline vary between machines. The same goes for any result logged only by a fitness app or watch. A treadmill is a great training tool for pacing practice, but the qualifying time has to come from a road race.

Virtual and GPS races

Virtual marathons, where you run your own route and upload a GPS file, do not count. GPS distance can be off by a quarter mile or more over 26.2 miles, the route has no certification, and there is no official timing. Many runners learned this during the years when virtual events were everywhere. Our post on why your qualifier must be on a certified course explains what certification checks.

Indoor, track and time trial marathons

Indoor marathons on a short track and small time trial events are also excluded, even when the distance is measured carefully. Boston wants a qualifier from a standard road marathon that is open to the public, not a specially arranged attempt. The same logic rules out handicapped races, where runners start at different times so that everyone finishes together, because your result does not come from a normal mass start race.

Shorter or longer races

Only the marathon distance counts. A fast half marathon does not convert into a qualifier, as we explain in can a half marathon qualify for Boston. Going longer does not help either: the marathon split inside an ultra is not an official marathon result, covered in does an ultramarathon qualify for Boston. Relay legs are out for the same reason.

Results that look valid but can still fail

A few cases catch runners off guard. A course that was cut short on race day, for example after a wrong turn by the lead vehicle, may lose its qualifying status for that year. A result run on someone else's bib, or without a bib, is not yours to submit. And the time must fall inside the window for the race you apply to. Boston checks your submitted time against official results, so the number on your watch does not matter; the official chip time does. See gun time or chip time for which one they use.

Why it matters more now

Even a valid qualifier is not a guaranteed entry. The 2027 race cut at 5:17 under the standard, after 4:34 for 2026, so you need a buffer as well as an accepted result. Finding out in registration week that your race does not count leaves no time to fix it. If you are unsure, check the race website for a certification number or ask the race director before you sign up, then put your expected time into the cutoff predictor to see how your buffer would have done against every real Boston cutoff since 2014.