Southern Rail reported a signalling fault at Hamble, which caused problems between Southampton Central and Fareham.
A statement from South Rail said: ‘The disruption between Fareham and Southampton has now cleared.
‘If your journey has been delayed by 15 minutes or more, please use Delay Repay to claim compensation.’
The initial fault was reported at 8.07am.
Passengers were warned their journeys could be cancelled, or delayed.
A statement from Southern Rail said: ‘A fault with the signalling system at Hamble is causing disruption to journeys between Southampton Central and Fareham.
‘As a result, trains between these stations may be cancelled or delayed by up to 10 minutes.
‘Please allow extra time to complete your journey this morning.
‘Your journey time will be extended and you may have to change trains in order to reach your destination.’
Tickets were accepted on alternative services, such as South Western Railway, at no extra cost.
Passengers are still advised to use the National Rail journey planner to keep updated with their journey.