The housebuilder is to add 90 houses at the site of the former NS&I offices off Preston New Road.
Rowland Homes is already on site delivering 115 homes on the 12-acre western part of the Blackpool site.
The next stage of the project on the 10-acre eastern plot can now begin following the signing of a Section 106 agreement with Blackpool Council.
Under the terms of that agreement, Rowland is to pay £125,000 in contributions towards healthcare and public open space.
An application lodged last year proposed the construction of almost 100 two-, three- and four-bedroom houses on 10 acres that formerly housed the offices of government-run savings bank.
Rowland had previously planned to deliver offices and industrial units on the site under an outline planning consent in 2016.
However, the housebuilder then opted to deliver more homes as there is “no reasonable prospect of the site being brought back into employment use”, according to a planning statement by the scheme’s consultant De Pol Associates.
The former NS&I buildings, including the eight-storey Premium Bonds tower, were demolished in 2017.
The tower was once home to Ernie – the Electronic Random Number Indicating Equipment that selects Premium Bond winners.