Arriva Trains Merseyside[1] was a train operating company in England owned by Arriva that operated the Merseyrail Electrics franchise from January 1997 until July 2003, when the Merseyrail railway franchise was transformed into the local Merseyrail concession, owned by the Merseyrail Passenger Transport Executive (Merseytravel).

The Merseyrail Electrics franchise was awarded by the Director of Passenger Rail Franchising to MTL with operations commencing on 19 January 1997.

[2] MTL retained the Merseyrail Electrics brand.

[5] On 23 April 2003, Serco-Abellio were awarded the Merseyrail Electrics franchise with the services operated by Arriva Trains Merseyside transferring to Merseyrail on 20 July 2003.

Arriva Trains Merseyside's fleet was maintained at Birkenhead North Depot.