The federal government spent $251 million on ads last year, fuelling criticism from integrity advocates about vote-buying as advertising industry players predict a surge in taxpayer-funded campaigns before the election.

Figures from the Department of Finance show ad spending leapt 40 per cent last financial year, as the Albanese government outlaid millions to publicise some of its signature policies such as the stage three tax cuts, Medicare urgent care clinics, and fee-free TAFE courses.