Plans for two unitary authorities to replace a cash-crisis council will be introduced a year later than planned.
Northamptonshire County Council's money problems in 2018 led to a plan to scrap it and seven other district and borough councils next year.
The scheme has been approved by government but the authorities will not be in operation until 1 April 2021.
Communities Secretary James Brokenshire said "shadow authorities" would be set-up in 2020 during a transition period.
These will be established following local elections in May 2020 - this month's local elections in Northamptonshire were cancelled.
As well as two new unitary councils, a children's trust will also be established to deliver services on behalf of the new authorities.
'Time to plan'
Mr Brokenshire's announcement brings to an end a long period of uncertainty over the future of local government in Northamptonshire.
The proposals were originally submitted to Westminster in August but local leaders had become worried Brexit was delaying the process.
Work will begin to see whether the unitary authorities can be formed in time for the intended deadline of April 2021.
Mr Brokenshire has also extended the initial deadline recommended by government inspector Max Caller last year in his report into the failing county council.
In a joint statement, the leaders of eight councils said the announcement "gives us more time to plan carefully and confidently for the future to ensure that we create two sustainable unitary councils".
Why unitary?
The unitary authority model means all council services will be under one roof, whereas the county council was in charge of services such as education, health and social care, while the borough and district councils looked after waste, recycling and planning applications.
Under the newly backed plans South Northamptonshire, Northampton Borough and Daventry will effectively merge to create the new West Northamptonshire unitary authority.
A second unitary authority - North Northamptonshire - will oversee Corby, East Northamptonshire, Kettering and Wellingborough.