The Wilko name will disappear from UK High Streets after a rescue deal for the chain fell through.
All of its 400 stores across the UK will close by early October, the GMB union has said.
It means redundancies are likely for all 12,500 staff at the family-owned business.
It is understood no bidders are interested in running shops under the Wilko name, although some parties are interested in rebranding their stores.
The billionaire owner of HMV, Doug Putman, hoped to keep up to 300 Wilko shops open, but his bid failed as rising costs complicated the deal.
This week will see the first Wilko stores close, after administrators PwC previously announced 52 shops across the country would cease trading on Tuesday and Thursday.
A further 124 stores will close between 17 and 21 September including sites in Bognor Regis, Humberstone in Leicestershire and Maidenhead (a full list is at the end of this article)
Wilko's distribution centre operations will wind down on 15 September
PwC said timings for the closure of the final 222 stores will be announced in due course.
Wilko has struggled with strong competition from rival chains like B&M, Poundland, The Range and Home Bargains, as the high cost of living has pushed shoppers to seek out bargains.
B&M has said it will take on up to 51 of Wilko's 400 shops in a deal worth £13m. The BBC understands that the stores will be rebranded as B&M shops, although it is not clear yet whether any jobs will be saved or if Wilko workers will be given preference if they apply for roles at the B&M shops.
Many Wilko shops are in High Street locations in traditional town centres. While these locations are convenient for shoppers without cars, since the pandemic there has been a shift to bigger retail parks and out-of-town options with more space, benefiting its rivals like B&M.
Poundland is also understood to be interested in buying up to 70 stores as a way of boosting its own portfolio.
The Wilko brand is also still up for grabs, with retailers including The Range proposing bids for the name specifically.
'Sick and tired'
One Wilko worker, who asked not to be named, told BBC News on Monday morning that staff still had not been given any official information on the future of her store.
"I feel sick and tired now, everyone is stressed," she said.
The employee, who has worked for the retail chain for 15 years, added that she felt "let down by Wilko, the union and the administration people".
Another said that they were finding out details from the press, adding that weeks of uncertainty had affected workers' mental health.
"This is not fair on these loyal employees who stuck by Wilko," she said.
The cash-strapped chain announced in August it had collapsed into administration, raising concerns over the futures of its 12,500 employees.
So far, 1,016 redundancies have been announced at stores that are closing.
Another 299 redundancies have taken place at its two distribution centres in Worksop and Newport, which will close on Friday next week, while more than 260 redundancies have been made at its support centre.
A rescue bid put forward by Canadian entrepreneur Doug Putman was hampered by the costs and difficulties thrown up by the need to overhaul Wilko's supply chains.
He had originally been eyeing up to 300 shops, but the deal in its most recent form may have included about 100.
Day-to-day costs to keep everything running, rents and supplier contracts were also posing a challenge.
Mr Putman said he had worked with administrators and suppliers over several weeks to seek a viable way to rescue the business and the failed bid was "a great disappointment".
"A stable foundation could not be secured to ensure long-term success for the business and its people in the way that we would have wanted," he added.
After the collapse of Woolworths in 2008, Wilko - which remained family-run until its problems came to a head - stepped up to fill the gap left on the High Street.
Are you a Wilko worker affected by this? Get in touch by emailing firstname.lastname@example.org.
Founded in 1930 and well known for its affordable everyday items, it had been struggling with sharp losses and a cash shortage.
Nadine Houghton, national officer at the GMB union, said: "Wilko was far more than a brand, a retailer or the products it sold, it was the thousands of loyal team members now facing an uncertain future. "Wilko may have ceased genuinely being a family brand many years ago, but the staff kept the real family ethos of Wilko alive until the very end. It is the family that Wilko colleagues made for themselves that will be missed the most."
Wilko had already borrowed millions from restructuring specialist Hilco, cut jobs and rejigged its leadership team and sold off a distribution centre as it struggled with rising costs and keeping shops fully stocked.
The company has been criticised for paying dividends in recent years, but Lisa Wilkinson, the retailer's chairwoman until January this year and the granddaughter of the firm's founder, said the company would have collapsed even if it had not made these payments.
Ms Wilkinson recently said "everybody has thrown everything" at trying to save the business.
Full list of Wilko stores to close next week
These 38 Wilko stores will close on Sunday 17 September:
Bognor Regis, West Sussex
Bradford, West Yorkshire
Bury St Edmunds, Suffolk
Crawley, West Sussex
Droylsden, Greater Manchester
Ellesmere Port, Cheshire
Kensington High Street, London
Kings Heath, Birmingham
Leigh, Greater Manchester
Market Harborough, Leicestershire
Melton Mowbray, Leicestershire
Orpington, Greater London
Pontefract, West Yorkshire
Sovereign Harbour, Eastbourne
Wimbledon, Greater London
Wombwell, South Yorkshire
Woodhouse Lane, Leeds
These 38 Wilko shops will close on Tuesday 19 September:
Hessle Road - Hull
These 48 Wilko shops will close on Thursday 21 September:
Clacton on Sea
Parc Trostre Llanelli
Tamworth Retail Park
Walton on Thames
Wheatley Retail Park