The Seafire Mk.XVII was the first to feature the cut down fuselage with the sliding teardrop canopy. The undercarriage was strengthened meaning a reinforced wing structure which enabled the Mk.XVII to carry larger payloads, rockets and drop tanks. It used the universal wing type e with one 20mm Hispano and two Browning .303 in each wing. The folding wing of the Mk.III was now standard for all Seafires. It was powered by a Rolls-Royce Griffon VI with 1,850hp driving a four blade Rotol propeller. The extended oleos of the new undercarriage drastically improved landing and take-off characteristics preventing the bounce and reducing the risk of the propeller hitting the deck on landing. These issues had plagued the Seafire from day one resulting in a disproportionate number of accidents and right-offs, not to mention pilot losses.

The Mk.XVII was an upgraded Mk.XV with 223 being produced however it was not in time for the war. The type entered service in late 1945. The FAA used the Mk.XV and XVII to replace the battered Merlin powered aircraft. The Mk.XVII Spitfires were supplied to eight FAA squadrons being used by 800 NAS and 805 NAS on HMS Triumph and HMS Ocean in the Mediterranean during 1947-48.  No.807 Squadron was equipped with the type in Germany 1945-46. It was retired from front line duties in 1951. The Mk.XVII was finally retired in 1954.

There are two surviving F Mk.XVII in the UK, one of which, SX336, is airworthy and owned privately in Cranfield. It was built by Westland in 1946. The other, SX137, is on static display in the FAA Museum, Yeovilton.