Another 80 Poundworld stores will be closed, resulting in 1,024 job losses, the company's administrators have said.
The latest announcement means that 105 of the company's 335 stores are now earmarked for closure.
Poundworld went into administration last month after failing to cope with rising costs, fewer shoppers and greater competition.
The company's administrators, Deloitte, said talks to sell remaining parts of the business continue.
"Whilst we remain hopeful that a sale for part, or parts, of the business can still happen, it has not been possible to sell the business as a whole," said administrator Clare Boardman.
At least two potential deals have failed so far, including one from the chain's founder Chris Edwards, who was offering to buy around half of the stores.
In June, Alteri investors, which specialises in buying struggling retailers, also pulled out of takeover talks.
Poundworld traces its origins back to 1974 and a market stall in Wakefield, West Yorkshire.
In 2015 Mr Edwards sold the chain to US private equity firm, TPG, which also controls restaurant chain, Prezzo.
In 2016-17 Poundworld reported losses of £17.1m, which was partly the result of tough competition from rivals including Poundland and Poundstretcher.
Like its rivals, Poundworld imports much of its stock from the Far East, so the sharp fall in the value of the pound after the 2016 Brexit referendum also hit profits.