Last month, BAA announced a new lottery for runners who met their Boston qualifying marathon time but did not make the cutoff. They will put 1,000 spots aside for these runners, suggesting that the odds of getting in this way will be about 8 to 10%.
But an interesting side effect of this lottery is that it could increase the percentage of runners who apply. In years where the cutoff is expected to be low or non-existent, runners who are closest to their BQ are the most likely to apply. The logic here is that these people are more likely to be targeting a BQ – and therefore likely to convert to an applicant.
For the last three years, I’ve estimated a conversion rate of how the number of qualifiers yields a number of applicants. This isn’t an actual conversion rate, because my sample doesn’t include every qualifier. But it represents the fact that based on a given number of qualifiers, the number of applicants will be X%.
In 2024, it was slightly higher (79.3%) for runners with 0-5 minute buffers compared to those with 5-10 minute buffers (78.6%). These numbers aren’t directly comparable to the data from 2025 and 2026, because I changed the methodology slightly to account for runners who had multiple BQ’s.
But in 2025, the conversion rate was 59.7% for the 0-5 group and 69.4% for the 5-10 group. The following year, it worked out to 64.9% and 66.4%. In both cases, that conversion rate was lower for the slower runners and (at least slightly) higher for the faster runners.
What If More Runners Apply?
One interpretation of this data is that these slower runners (especially the ones with 1-2 minute buffers) are less likely to apply because they are now expecting a big cutoff. If that’s the case, the conversion rate for these slower runners should increase this year – since applying will now bring with it a chance to enter through the lottery.
We don’t have all of the data yet, but by projecting forward what we currently have and assuming the same conversion rates as last year, the number of applicants would be ~33,200. Note that this exact same methodology applied to last year’s data through the current date yields a slight underestimate (32,750, compared to 33,249 actual applicants).
If we instead adjust the conversion rate for the slower runners to 70%, we get ~33,950 applicants.
And if we adjust the conversion rate up to 80% – probably a high end estimate of what’s possible – the number of applicants would be ~35,300.
So the incentive for these slower runners to apply could increase the total number of applicants by about 2-6%. But it likely still wouldn’t push it into crazy territory (like 40,000+).
What If There’s Another Explanation?
Looking back through the data, I’m now realizing there might be a different explanation for this phenomena. The numbers above required some adjustment due to the way the BAA reports the data.
But when you look at applicants to the 2026 Boston Marathon, the runners with a qualifying time between the cutoff (6:51) and 10:00 had a much higher conversion rate – 87.5%.
This suggests that there might be something else happening. As a core assumption, it would seem logical that the runners who are targeting Boston would have the highest conversion rate. Initially, I assumed that was runners targeting a BQ or a few minutes below.
But it’s possible that the runners targeting Boston have shifted their goal. And as a result, runners with a 5-10 minute buffer may be the most likely to apply. And it’s not so much that the slower runners think they won’t get in. It’s that they weren’t (as likely to be) motivated by Boston in the first place.
When you look at the data a different way, there has been a shift. In 2024, the number of runners with 5-10 minute buffers was ~75% of the number of runners with 0-5 minute buffers. But the following two years, once big cutoffs seemed to be more expected, the number of runners with 5-10 minute buffers was 90% of the number of runners with 0-5 minute buffers. There was much less of a gap.
And so far this year, that ratio has dropped to 96.5%. There are about 13,500 runners with 5-10 minute buffers and only about 14,000 runners with 0-5 minute buffers.
This could represent a further shift towards targeting faster times. And if that’s the case, that 5-10 minute group will likely still have a larger conversion rate because they’re the ones most likely to be targeting Boston.
If that’s the case, the boost to the number of applicants will be much lower. We’ll have to wait and see how many people apply – and that’ll help us understand which of these two explanations fits reality.