Opal's weekly travel handout is tapping out.

From Monday, Opal cardholders who have reached their eight paid trips in a week will have to pay half-fare rather than receive the current free trip reward.

Francesca Wallace, 21, says with travel costs already "through the roof in Sydney" she will be using other alternatives to public transport.

"As someone earning a pretty average low wage, I rely on these free trips to get around on the weekend," she said.