London Marathon offers non-binary option for mass event
Organisers said it was part of a drive to make the race the "most diverse, equitable and inclusive marathon in the world".
Three gender options - male, female and non-binary - will be offered to all participants registering for the mass participation element of the event.
"The elite athlete races, plus the Championship and Good For Age categories, which all operate under World Athletics rules, will not offer a non-binary gender option," organisers added in a statement.
Event director Hugh Brasher said it was a "significant step forward" in the drive to make the event more inclusive.
"We know there is still much more to be done, but changes such as this demonstrate our commitment to making the TCS London Marathon an event that is for everyone," he said.
The Boston Marathon announced a similar change this week.
The 2023 London Marathon will return to its traditional April slot for the first time in four years after it was disrupted by the coronavirus.
The ballot for those who want to take part in next year's event opens on October 1, the day before the 2022 London Marathon.