President Emmerson Mnangagwa last month announced a 6 p.m. to 6 a.m. curfew, but according to Information Minister Monica Mutsvangwa, this had left commuters stranded without transport.
The overnight curfew will now start at 8 p.m., while business hours will be extended to 4.30 p.m from 3 p.m.
Officials fear a wholesale removal of restrictions on movement would see a spike in infections and overwhelm a health sector that is collapsing due to strikes by workers and lack of medicines and protective clothing.
Zimbabwe has recorded 5,308 cases and 135 deaths.
