Arriving in the River Mersey on 28 April 1951, it was initially owned and operated by Wallasey Corporation and carried the borough coat of arms on the front of the superstructure.

[3][5] Originally painted in a green and cream livery, the ship was distinctive in having a forward dummy funnel near the bridge and two exhaust stacks amidships, on both sides.

Onboard amenities included a dancefloor and stage, tea room, buffet, cocktail bar, even a fish and chip saloon.

Paul McCartney referenced performing with the Beatles on the ferry in his song "That Was Me"[5] Royal Iris transferred to the combined fleet of the newly formed Merseyside Passenger Transport Executive on 1 December 1969, which consisted of seven vessels.

[9] During 1984 Royal Iris and the other three Mersey Ferries received the red, white and blue livery to mark the 1984 International Garden Festival at Otterspool.

It was sent on a 1500-mile round trip to London on a publicity drive for Merseyside, sailing around Land's End, up the River Thames and under Tower Bridge, docking adjacent to HMS Belfast.

The ageing Royal Iris, the last ex-Wallasey vessel, was considered surplus to requirements because of the cost of bringing it up to modern standards after a major survey.

On 21 April 1991, the boat was granted a one-day licence from the Department of Transport to carry 600 people on a cruise to mark the 73rd Anniversary of the Zeebrugge Raid of 1918.

[8] It was delivered to the Stanley Dock complex in early 1992 to begin a new life on Merseyside and was subsequently painted Bright Blue with a red band around the top deck windows.

[10] On 7 August 1993, the Liverpool Echo carried front page news that Royal Iris had been sold to Hertfordshire-based Parkway Leisure who had the intention of turning it into a floating nightspot in Cardiff, spending £300,000 on refurbishments.

[2][5][15][16] On 6 February 2010, it was reported that Police and the RNLI had been called out to the berth on the River Thames, near Woolwich, after a passing vessel noticed it had taken on water up to the passenger deck.

In July 2020, the Royal Iris was seen in background of Tony Robinson's programme Britain's Greatest River during delivery of Selina tunnelling boring machine to Chambers Wharf.