Norway's Solstad Offshore has fixed a platform supply vessel (PSV) for up to four years.
The company said its 6,400-dwt Normand Skipper (built 2005) will work for oil major Equinor for two firm years from November or December this year.
Two years of options are attached, but no rate was given.
Equinor has also exercised a one-year option on its contract for the 4,500-dwt PSV Sea Falcon (built 2013), effective from this month.
Normand Skipper will join this unit and another vessel in supporting the oil company's UK operations.