Younger people at high risk from Covid, as well as health and social care staff, will also get the booster.
Drug companies have been developing updated vaccines to tackle newer variants, however, it is still uncertain which vaccine will be used.
The original plan meant healthy people aged 50-65 would not have been jabbed.
However, the immunisation campaign has been expanded as current variants are spreading quickly, it is uncertain how the virus will mutate and it is expected we will be more social this winter than in previous years so the virus will have more chance to spread.
The updated advice comes from the Joint Committee on Vaccination and Immunisation (JCVI), which advises governments in England, Scotland, Wales and Northern Ireland.
It says the booster should be offered to:
* health and social care staff
* everyone aged 50 and over
* carers who are over the age of 16
* people over five whose health puts them at greater risk, this includes pregnant women
* people over five who share a house with somebody with a weakened immune system
The details of the rollout have not been confirmed, however, it is thought immunisation will start with the oldest and most vulnerable from September.
For some people it will be their sixth dose of a Covid vaccine.
Prof Anthony Harnden, the deputy chairman of the JCVI, said: "The Covid-19 boosters are highly effective at increasing immunity and, by offering a further dose to those at higher risk of severe illness this autumn, we hope to significantly reduce the risk of hospitalisations and deaths over the winter."
The current wave of Covid - caused by the sub-variants of Omicron BA.4 and BA.5 - demonstrates the speed the virus can spread. It is the third wave of Omicron subvariants this year and one in 18 people in the UK are currently testing positive.
Prime Minister Boris Johnson said: "Today we have confirmed the next phase in our booster programme to keep our defences strong over autumn and winter.
"Vaccines were our way out of this pandemic, and now they will make sure Covid can never haunt us in the same way again."
The flu vaccine in England will also be offered to all adults aged 50 and over, the usual high-risk groups and now to schoolchildren up to Year 9 in secondary school.
The Covid restrictions have meant we have barely had a flu season since the pandemic started. However, the concern is this year could be the first time we face substantial waves of both viruses at the same time.
Dr Mary Ramsay, the head of immunisation at the UK Health Security Agency, said: "Widening the eligibility for the flu vaccine will help reduce the number of people getting seriously ill and ease pressures on the NHS, particularly during the busy winter period."