The victim was on the train on May 28 at around 6.20pm when a man sexually assaulted her before leaving the train at Warrington Bank Quay Railway Station.
If you recognise him or have any information, text 61016 or call 0800 40 50 40 and quote reference 159 29/05/22.
You can also call Crimestoppers anonymously at 0800 555 111.
