Currently there are four Frankie & Benny's in Sussex - Chichester, Brighton, Eastbourne and Crawley - plus the Tex-Mex themed Chiquito in Crawley.
Frankie & Benny's, an Italian-American-themed restaurant, had been due to move into the Eastbourne Beacon development but pulled out.
In a statement, a spokesman for The Restaurant Group (TRG), which owns the two food chains, said he could not comment on the future of individual restaurants.
However, he confirmed that on top of the 76 Frankie & Benny's that had been earmarked as being in 'structurally unattractive locations' back in March, the company had now 'identified a further 42 sites across our other Leisure Brands, principally Chiquito’s and some other smaller ones, that are also in structurally unattractive locations.'
The 118 restaurants - 76 within Frankie and Benny’s and 42 Chiquito and other leisure sites - make up around a third of its restaurant portfolio.
The company has also said it expects to close 'at least 50 per cent of Leisure sites' when the leases are up. This means that during the next six years it plans to close approximately 88 restaurants, with those on longer leases also under threat of closure.
In a statement the spokesman said: "In our half year results we announced to the stock market today, we stated that the backdrop remains challenging for our Leisure division, comprising principally Frankie and Benny’s and Chiquito’s.
"Responding to these headwinds in the casual dining market we stated that we expect to exit at least 50 per cent of Leisure sites reaching their next exit date.
"We want to stress that we are by no means committing to the closure of all these sites and certainly not with any immediacy.
"Our Leisure sites have an average of six years to their first potential exit date, so as and when leases do come up for renewal, we will take a considered and disciplined approach, on a case-by-case basis. When and if we do close sites we will always look to redeploy staff to other sites within our portfolio."