The shop will open a new branch in The Galleries next week.
Thirty jobs will be created thanks to the new shop opening - with further vacancies expected for the Christmas period.
The discount chain store will come to Washington on October 29. The doors will open to the public at 10am, on the site of the former post office.
Cheryl Galloway is store manager. She said: "We're thrilled to be opening at The Galleries Shopping Centre, breathing life into the old post office and creating 30 new jobs in the process.
"We offer huge savings to over two million customers every week and we’re excited to be able to offer that same incredible value to Washington locals.”
In honour of the shop's opening, there will be fun and games happening for all the family - including a visit from the Poundworld mascot and face painting.
If you want to apply for retail opportunities over the Christmas period, contact firstname.lastname@example.org