What it will take to qualify for the 2021 Boston Marathon

Adam Wolfberg, MD
4 min readMar 28, 2021

What a year! In the context of the pandemic, BQ minutia is genuinely trivial, but with that in mind, let’s address a question that is preoccupying a few thousand of us non-elite runners: How far below the 2021 Boston Qualifying Time (BQT) do I need to run in order to line up in Hopkinton on October 11, 2021?

You likely know this: The Boston Marathon was cancelled in 2020 and qualifying times were not changed for 2021, but the field size will be reduced from 31,500 to 20,000, and the field of qualifiers (~20 percent of bibs go to invitees and charity runners) will be reduced from 24,350 to 16,000.

For the 2020 race, 3,161 qualifiers did not get a bib, based on a threshold of 1:39 under the BQT, suggesting that 27,511 runners applied in 2020 having run BQTs between September 15, 2018 and September 2019 when registration opened. Leaving all other variables aside (I’ll come back to those), the number of qualifiers will have to be reduced from 27,511 to 16,000 or 42%.

Predicting how far under BQT you need to run to get a bib:

It is not surprising that qualifiers are more likely to run times near their BQT than they are to run elite-level times. For example, there are more 50-year-old male runners with times between 3:20 and 3:25 than there are with times between 3:00 and 3:05. It would seem intuitive, therefore, that for each additional second under the threshold, the BAA cuts fewer and fewer runners.

I plotted qualifiers cut and the time under the BQ threshold, anticipating to see diminishing returns for each additional time increment under the threshold, however at least for the first five minutes under the threshold, the curve appears essentially linear (data from the BAA website).

Based on an average of, 30.1 qualifiers cut per second under the BQT over the past eight years, the time to get a bib in 2021 would be 6:22 under qualifying time.

Adrian Hanft has done some nice work quantifying BAA data on Medium, and on his site, the Boston Marathon Data Project. On that site, the principle of diminishing returns is apparent: approximately twice as many qualifiers run times 0–10 minutes under the BQ threshold, as run times 10–20 minutes under the BQ threshold. Eyeballing Adrian’s pie chart of qualifying times for 2020, 42 percent of qualifiers would be cut with a time 7–9 minutes under the BQT.

Recognizing that unknown variables will determine the number of qualified applicants, the Boston Athletic Association (BAA) changed its application process this year, creating a single application window. Here are some of those variables, which I’ve categorized by my opinion on whether they lower the time needed to get a bib or raise it:

Factors that I think will lower the time needed for a bib:

Aging: Most BQ runners are age-groupers, and 20 percent of us gained time by aging into the next category (I turned 50 last year, so get five more minutes in 2021 than I did when I qualified in 2020).

The qualifying window is six months longer: All of the races run in the fall and winter of 2019–2020 (until races closed down for the pandemic in March 2020) count this year, in addition to those run in the year from fall 2018 through fall 2019.

I can’t wait to toe a starting line after the year we’ve had: A few races are scheduled, but not many. I could imagine that anyone with a qualifying time who’s been itching to race will sign up.

Factors that I think will raise the time needed for a bib:

Another year: Presumably, some people moved on from racing, and just aren’t up for the Boston Marathon this year. There is no underestimating the toll that the past year has had on runners and everyone else.

Travel: The Boston Marathon is truly an international event — a celebration of running on a global scale. I can imagine that runners from other countries who are still experiencing travel restrictions may be reluctant to sign up for a race they may or may not be able to attend.

What’s my guess? I’m betting that the time-lowering factors will outweigh the time-raising ones, and the cutoff will be 10:30 below qualifying times. I’ll update this in late April when registration is complete and this post’s relevance has expired. Good luck to all of you who are hoping — like I am — to finally get that elusive bib.