It follows pressure from residents who have called for the city's two tips to be open for longer.
Council bosses also hope the decision will help combat fly-tipping.
The site on Shaw Road, Bushbury, will be open later into the evenings on Mondays and Tuesdays, while hours at Anchor Lane, Lanesfield, will be extended on Mondays and Fridays.
Shaw Road will also open until 7pm on Wednesday while Anchor Lane will open until 7pm on Thursday.
Changes will come into force from Monday and continue until winter when opening hours will revert back.
City environment boss Steve Evans said the authority had "listened" to calls for extended hours and said the move would not cost any more.
He said it would mean people have more time to dump rubbish after work rather than at the weekend, when queues are regularly seen.
The Shaw Road tip will stay open an extra hour on Mondays until 5pm and an extra two hours on Tuesdays until 6pm.
Both will remain closed two days a week. Anchor Lane will be open an extra hour on Mondays until 5pm and an extra two hours on Fridays until 6pm.
Councillor Evans said: “Residents have told us they want the tips to be open for longer, we’ve listened to their feedback, and acted upon it.
“It would be great to be able to say we can have tips open seven days a week, but it’s simply not possible within the financial constraints.
"I’ve re-looked at the way the sites work and pushed resources as far as possible with no additional cost implications.
“I’m sure the extended hours will help, especially because both sites will be open in the evening until 7pm.
"The longer lighter evenings mean people can use the facilities after work, rather than having to use their weekend to get their recycling and decluttering done.
“Extending the opening hours also means there is no excuse for fly-tipping in our city.
"Those who chose to ignore this, will be caught, their vehicle seized, and prosecution will ensue.”