The new measures total 4.6 billion pounds - or about 6.2 billion dollars.
Set out by finance minister Rishi Sunak Tuesday (January 5), they mean companies in retail, hospitality and leisure can claim one-off grants worth just over £9,000, or about $12,000.
"It's important to remember that comes on top of existing monthly grants of 3,000 pounds that those businesses receive and the extension of furlough all the way through to April, you know, we remain committed to protecting jobs and supporting businesses."
Last year, Sunak announced emergency help for the UK economy worth around $380 billion.
It included a massive job protection scheme due to run to the end of April.
The country will likely need it, with J.P. Morgan analysts predicting a hefty 2.5% fall in output for the first three months of this year.
Britain's new lockdown was announced on Monday (January 4) by Prime Minister Boris Johnson.
It means most people must work from home, and sees schools closed for almost all pupils.
Hospitality venues and non-essential shops must stay shut.
UK-based airlines British Airways and easyJet are among the first to suffer.
Both carriers said they were reviewing their plans in response to the lockdown.
A reduction in flights seems almost certain, with most Britons now prevented from travelling abroad.
