Engineering work is taking place between St Albans City and Harlington , closing some lines.
Thameslink services between Brighton / Horsham / Three Bridges and Bedford, and trains to / from Sutton will run to a revised timetable.
A reduced service will run between London and Luton / St Albans.
Check before you travel:
If you are travelling with Thameslink, you can plan your journey using the National Rail Enquiries Journey Planner
If you are travelling with East Midlands Railway, these changes are not currently shown in the National Rail Enquiries Journey Planner, please check back nearer to the time of travel.