The Grade-I listed landmark, which has been owned by the council since 2010, needs "essential" strengthening work to be carried out on its steel structure.
A council report says a continuing £6m steel renovation project has cost extra money, but the loan will be recouped from the income of leisure assets.
Councillors will consider the proposal on 20 July.
Deputy leader of Blackpool Council Gillian Campbell said the tower was "a vital asset to town" which the council was "committed to keep in a good condition".
"Our acquisition of the tower was all about making sure it is looked after for many years to come and this work will make sure that continues to be the case," she added.
The seafront tower opened in 1894 and its design is inspired by the Eiffel Tower in Paris.
Councillors in Blackpool are to be asked to approve borrowing of £1.8m to repair the resort's tower.