Platform 1 is a through platform used as a bay platform by Great Western Railway's terminating local trains to Oxford and commuter trains beyond to Reading and Paddington, and by Chiltern Railways through and terminating services from the south – all terminating trains at this platform travel a short distance up the line before reversing back to the same platform and boarding outbound passengers, unless a train has since occupied the platform, which then means the train reverses to platform 3 to board passengers, It is also used as an emergency through platform if one of the others is out of use for any reason.