Genworth Mortgage Insurance has renewed its contract to supply lenders’ mortgage insurance to NAB.

The contract had been due to expire in November but will now run until November 2017, with a 12-month extension option, Genworth told the Australian Securities Exchange.

NAB business represented 11% of Genworth’s gross written premium (GWP) last year.

Genworth’s shares slid 20% to $3.305 in February after it announced it had lost its contract with Westpac, which accounted for 14% of GWP.

The shares were trading at $3.15 this morning.