Nearly 60 victims of the 2011 Margaret River bushfire have joined a class action against the Department of Environment and Conservation.

The bushfire on November 23-24 last year spread from a prescribed burn by the DEC that got out of control, destroying more than 40 properties in the south-west tourism and wine-growing region.

Law firm Slater and Gordon last month said it had received sufficient interest from bushfire victims to launch a class action and urged others to get in touch before October 5.

Commercial and project litigation general manager James Higgins said nearly 60 people had signed up.

"Home and business owners were devastated by the prescribed blaze which burned out of control in the State's south-west and it's important that we fight for adequate compensation," Mr Higgins said.

Friday was the deadline to sign up, but the firm said it still expected a last-minute rush of clients.