Frozen food specialist Iceland is relocating to the shopping centre from its current Weldale Street store in the town centre.
It has agreed a 10-year lease on a 9,000 sq ft unit.
Poundland is taking on a 8,500 sq ft property, occupying the former Poundworldstore and an adjoining unit on Oxford Road.
The trio of new deals is completed by New Look, which has renewed its lease having previously said it was quitting the location.
New Look is also relocating its menswear proposition into the Broad Street Mall shop from its other Reading store in the Oracle.
Gary Lewis, managing director of Broad Street Mall owner Moorgarth Group, said: “This series of deals is testament to the appeal of Broad Street Mall and demonstrates that Moorgarth’s strategy of modernisation and broadening of the offers on site is attracting considerable attention.
“We look forward to welcoming more new arrivals to the centre soon.”