Bus passengers faced severe disruption to their journey home as drivers took part in a 24-hour strike over pay.
Many bus services have been affected by the strike
Some 60 bus routes serving north, central and west London and parts of Hertfordshire have been affected.
The Transport and General Workers' Union wants a 6% wage increase in line with similar pay offers from other London bus operators.
Metroline has offered a 4% pay rise and said it believed this was "still the best deal in London".
The strike, which ends at 0400 GMT on Wednesday, has affected routes out of King's Cross, Wembley, Holloway, Perivale, Edgware, Willesden and Cricklewood.
Main routes hit included the 134, 139, 24, 263, 82 and 113 as well as many night bus routes to North London out of Trafalgar Square.
Jack Dromey, of the Transport and General Workers' Union, said the industrial action was a last resort after negotiations stalled.
Drivers want an increase to their basic salary from £10.43 an hour to £11.
"If other bus operators can find up to 6% why can't Metroline?" said Mr Dromey.
A Metroline statement said the pay offer was "fair and reasonable in the context of recent improvements to pay and our current financial performance".
"The company remains committed to resolving this dispute," it said.
Further strikes will be held on 20 and 27 November unless the deadlock is broken.