South Kesteven District Council has also confirmed that it plans additional services from 7 September with an online click and collect book service and essential council appointments.
From Monday, library members can return books to a desk at the entrance or into a drop-box outside to enable social distancing to be maintained.
Book drop-offs and computer sessions will be available on Mondays, Wednesdays and Fridays from 10am to 1pm. Customers who wish to access a library PC must pre-book a slot online through Lincolnshire County Council on 01522 782010.
Cllr Rosemary Trollope-Bellew, SKDC Cabinet Member for Culture and Visitor Economy, said: "It's very important to see our key services restored, but it's also vital that we do so safely.
"The systems we have put in place are designed to make sure we do not contravene social distancing guidance, while restoring some key library services, namely access to computers and book returns."
From September the library's click and collect book service will operate with online reservations to collect books at a pre-arranged date and time without going in to browse.