The Prime Minister said “tens of thousands” of volunteers were needed as the vaccination programme is ramped up to an unprecedented pace of delivery.
They range from stewards to organise and manage the queues to trained vaccinators to administer the jabs.
It follows the announcement on Sunday that every eligible adult in England is to be offered a top-up injection by the end of December, a month earlier than previously planned, while resources are being made available to the devolved nations to speed up delivery.
It reflects concern that two doses of the vaccine offer only reduced protection against the fast-spreading Omicron strain while a third jab significantly increases the protection provided.
Mr Johnson has acknowledged that it will require an “extraordinary effort” by the NHS with hundreds more vaccination sites, mobile units and pop-ups due to open over the coming week.
In a direct appeal to the public, Mr Johnson said: “As part of our Get Boosted Now vaccination drive we need to increase our jabbing capacity to unprecedented levels.
“But to achieve something on this scale, we need your help.
“So today I’m issuing a call for volunteers to join our national mission to get jabs in arms.
“We need tens of thousands of people to help out, everyone from trained vaccinators to stewards.
“Many thousands have already given their time but we need you to come forward again, to work alongside our brilliant GPs, doctors, nurses and pharmacists, to deliver jabs and save lives.
“So please come forward if you can.”
There currently almost 3,000 vaccine sites across the country, staffed by over 90,000 volunteers.
After the NHS last week announced a recruitment drive for 10,000 paid vaccinators, 4,500 people have registered their interest while 13,000 have come forward as volunteer stewards.
NHS England chief executive Amanda Pritchard said: “In the face of the grave threat posed by the new Omicron strain of Covid, the NHS is seeking to offer vaccine booster protection to all eligible adults by the end of the month, a new national mission in which everyone can play their part.
“There is no doubt that our incredible NHS staff will rise to the challenge but we cannot do this alone, we need the support of the public and volunteers to once again support the Covid vaccination programme.”