Drivers and rail workers on South Western Railway will go ahead with two days of strike action in a long-running dispute over guards on trains.
The Rail, Maritime and Transport Union (RMT) announced strike action for Thursday and New Year's Eve.
On Saturday RMT members held strikes over the dispute with South Western Railway, and Northern Rail.
South Western said it would run a reduced service across the network, with some lines having no service.
The two 24-hour strikes are expected to affect transport for Christmas shoppers and new year revellers.
Some rail replacement bus services will be in place, but South Western has advised passengers on some parts of the network to seek alternative transport.
The RMT has said South Western will be reimbursed for revenues lost as a result of the strike action.
General secretary Mick Cash said the "strike bailout" could be worth more than £26m to the rail franchise, adding it would be "enough to fund a 2019 fare cut for all South Western passengers".
The union said former rail minister Jo Johnson had admitted to MPs that South Western had made an application to be reimbursed.
Which services are affected?
- Basingstoke to London Waterloo: Reduced service with one train an hour running in each direction
- Salisbury to London Waterloo: An hourly reduced service will run
- Guildford to Ascot: A bus service will be in operation
- Portsmouth to London Waterloo: Due to planned engineering works there will be a reduced service and rail replacement services between Woking, Guildford and Haslemere
- Portsmouth to Southampton: Trains will run between Southampton Central and Fareham, with one service every two hours
- London Waterloo to Reading: Two trains an hour will run between Clapham Junction and Reading
- London Waterloo to Weymouth: Hourly trains will run between Waterloo and Bournemouth, with a shuttle service between Bournemouth and Weymouth
- Salisbury to Romsey via Southampton: No services
Elsewhere, the RMT union has also instructed conductors, conductor instructors and train driver members on Northern to take action on Saturday 5, 12, 19 and 26 January.