The collapse puts more than 5,000 jobs at risk, making it the biggest retail insolvency so far this year by job numbers.
The budget retailer is poised to appoint Deloitte to handle an administration after last-ditch rescue talks with R Capital broke down over the weekend.
Clare Boardman, joint administrator of Poundworld, said that the chain had been affected by the "challenging" retail environment.
Poundworld, which is owned by TPG Capital, has 335 stores.
The appointment of Deloitte as administrators leaves the future of five stores in the county hanging in the balance.
The filing provided it with protection as it looked to secure a deal, which would lead to store closures and an administration process, allowing its staff and suppliers continue to be paid.
"Unfortunately, this has not been possible".
Administrator Deloitte hopes to find a buyer for Poundworld, which also trades under Bargain Buys, and ruled out instant redundancies or store closures.
The chain has a store at the Richmond Centre in Derry.
Many of these have been struck this year as retailers have struggled with surging costs, rising business rates, competition from online rivals and a slowdown in consumer spending.
A TPG Capital spokesman said: "This was a hard decision for every party involved".
Poundworld's possible collapse comes after both Toys R Us and Maplin both fell into administration earlier this year. Losses reportedly jumped to £17.1million in 2016 to 2017, from £5.4m the year before.
"Despite investing resources to strengthen the business, the decline in United Kingdom retail and changing consumer behaviour affected Poundworld significantly".
The news comes hot on the heels of House of Fraser revealing it was to close more than half of its United Kingdom stores in a bid to make it viable.