From Tuesday, September 1 concessionary bus pass holders can only use their bus passes from 9.30am on weekdays but can continue to use them any time at the weekend.
This means Wiltshire falls in line with local authorities in the rest of England in reintroducing allotted times for the scheme.
Cllr Bridget Wayman, cabinet member for transport said: "From September 1 the council is reintroducing the 9.30am scheme start time on weekdays, in order to ensure there is enough capacity on the network at peak times for the return of school and college students.
"Bus operators have been notified of this change, and bus passes will not be accepted on ticket machines before 9.30am unless travelling on an infrequent exempted route.
"In March we took the decision to relax our Concessionary Fare Scheme times so that concessionary bus pass holders were able to make essential journeys to shops and health appointments before 9.30am during the peak of the Covid-19 pandemic.
"As schools go back and many people return to work this is a good time to reintroduce the time restriction so transport and social distancing can be managed effectively."