Perth drivers are being encouraged to fill their tanks this afternoon ahead of a 19-cent per litre price increase on Tuesday.

The cheapest fuel available in the metropolitan area on Tuesday will cost 99.4c per litre at Caltex Woolworths in both Greenwood and South Lake.

The average petrol price on Tuesday will be $1.22 per litre. Monday’s average was 102.5c per litre.

Perth’s cheapest days for petrol are Sundays and Mondays, while Tuesdays and Wednesdays are generally the most expensive.