Restaurant chains Zizzi and ASK Italian are set to close 75 outlets putting 1,200 jobs at risk.
Azzurri Group, the owner of the two chains, was pulled from administration by US investment firm TowerBrook Capital Partners.
As part of the deal 225 restaurants and shops will remain open, saving around 5,000 jobs - but 75 branches will not reopen.
The company said the coronavirus pandemic had devastated the hospitality trade.
"The COVID-19 crisis has had a profound impact on the casual dining sector, bringing many businesses like ours to a standstill," said Steve Holmes, chief executive of Azzurri Group.
"Despite being a successful operator, the immediate loss of revenue during lockdown meant that we have had to make some incredibly difficult decisions to protect the business for the long-term.
"It is with deep sadness that this process will result in the permanent closure of a number of sites and that we must say goodbye to greatly valued employees across our brands."
More than 88,000 jobs have been lost due to the pandemic, with at least 12,000 being axed from the hospitality sector.
Last month The Restaurant Group (RTN.L), which owns Frankie and Benny's, said it planned to shut 125 sites with the loss of up to 3,000 workers. And Pizza Express is expected to announce the closure of 75 restaurants imminently.
Meanwhile the Casual Dining Group, which owns Bella Italia, Cafe Rouge and Las Iguanas; Carluccio's, Pret a Manger and Le Pain Quotidien, is set to cut 1,900 jobs by closing 91 of its 250 restaurants after calling in administrators.