People aged 65 and over can now book their Covid-19 booster jab online or via 119.
The NHS is also offering appointments to carers and pregnant women as the vaccine rollout continues into the cooler months.
People aged 75 and over, the severely immunosuppressed and frontline health and care workers have been able to book a booster since last week.
Bookings can be done online or over the phone as long as the person had their last Covid jab at least three months ago.
Around 26 million people in England will be eligible for an autumn booster in the comings weeks.
NHS director of vaccinations and screening Steve Russell said: “There is no room for complacency in keeping Covid-19 on the back foot and this autumn booster will help protect those most at risk.
“From today those aged 65 and over, pregnant women and carers are now able to get their jab.
“If you are one of those eligible, it is as important as ever to get your next dose, so please do come forward as soon as possible.”
Dozens of hospital hubs are joining the rollout to administer the jab – plus flu vaccines where possible – to members of the public as well as NHS staff.
Eventually, all those aged 50 will be offered a vaccine.
Two vaccines have been approved that can be used as boosters this autumn and winter – one from Moderna and the second from Pfizer.
Both have been approved by the Medicines and Healthcare products Regulatory Agency (MHRA) to target both the original and Omicron strains of the virus.
People who qualify for an autumn/winter booster include adults aged 50 and over, those aged five to 49 with health conditions that put them at greater risk, pregnant women, care home workers and frontline health and social care workers, carers and the household contacts of people with weakened immune systems.
It comes as the Office for National Statistics said that Covid-19 infections have continued to fall in England and Wales while the trend is uncertain in Scotland and Northern Ireland.
A total of 944,700 people in private households in the UK are estimated to have had coronavirus in the seven days to August 28.
This is a drop of 12% from 1.1 million in the seven days to August 23 and is the lowest total since the week to October 2 2021.