On 1 July 2006, it was merged to the single Yorkshire Ambulance Service.

In 1992, it became an NHS Trust, providing 24-hour emergency and healthcare services to more than 2.1 million people across the region.

[1] WYMAS covered the whole of West Yorkshire, including the cities of Bradford, Leeds, and Wakefield, and the towns of Halifax, Huddersfield and Pontefract.

In addition, WYMAS's coverage extended into the Craven area of North Yorkshire with ambulance stations at Grassington, Ingleton, Settle and Skipton, covering the western side of North Yorkshire and the Yorkshire Dales.

There were 21 ambulance stations situated across the WYMAS operating area.