London tube operating hours are different during workdays and weekend. There are different timetables for each tube line.
For example, Central line operating hours can be splitted into:
You can find information that tube starts from around 5 AM during workdays. On weekend it starts around 1 hour later.But in case of some tube lines, there is also a night tube operating.
- Monday - Thursday
It operates on Friday and Saturday nights. You have to check the night tube map and timetables.
So for example, on the Northern line, tube starts "earlier" on Saturday and Sunday morning. It actually runs a 24-hour service.