You will be given the chance to select your T-shirt size in the run-up to the event. If it does not fit when you receive it after crossing the Finish Line and you would like to exchange it, please send your T-shirt, along with a note including your full name, bib number, preferred T-shirt size and full postal address, to:

London Marathon, C/O Sarah Plunkett,
Unit D1, Adanac North Business Park,
Adanac Drive,
Southampton, SO16 0BT

We will then send you the requested T-shirt within two weeks.