Two new rules will be implemented in 2021:

TOP 50 PERCENT AGE GROUP RULE
Beginning in 2021, adult racers will need to finish in the Top 50 percent of their age group to earn priority registration in 2022. This replaces the First 225 Finishers Rule and is intended to increase the number of lottery spots and improve lottery odds. Those with 10-Year Status are not impacted.

10-YEAR NEW RACER REPEAL RULE
Beginning in 2021, new racers will not be eligible to earn Priority 10-Year Status. Those who have previously completed an adult race remain eligible. This change will gradually increase lottery selection odds (beginning in 2030).

These rules, and several others, were approved by the Mount Marathon Race Committee in February 2020. They were announced at that time and published on the race website.

There are a few exceptions. Frequently Asked Questions about these rules.