Job advertisements in Sydney and Melbourne are falling at double digit rates, prompting concern unemployment may be increasing despite cuts in official interest rates and the Morrison government's tax cuts for low and middle income earners.

Figures to be released today by SEEK show overall job ads have fallen by 8.6 per cent over the 12 months to the end of August. There had been signs of a slight improvement in July but that was swept away through the final month of winter.

Job ads have fallen by 8.6 per cent over the past year, according to SEEK, with double-digit falls in Sydney and Melbourne. Credit:Louise Kennerley

Ads in the nation's biggest job market, Sydney, have now fallen by 16.9 per cent over the past year while in Melbourne they have dropped by 11.9 per cent.

Every capital city bar Canberra and Perth now have job advertisements, an early indicator of the jobs markets, falling over the past year.