Job Centre Plus and a gym are the new arrivals.
More than 90 new jobs will be created.
Stuart Mitchell, director at NewRiver REIT, owner of Priory Meadow, said: “Following the economic impact of Covid-19, it is great to be able to repurpose and regenerate this former retail unit into office and gym uses.
“The Job Centre Plus will provide an important service as we bounce back from the pandemic, giving the opportunity to improve the financial circumstances of residents in the Hastings community.
“We are also pleased to announce that the first floor of the same building is in the final negotiation stages with a national gym operator, which will attract additional footfall and a new demographic to the centre and activate surplus upper floor space.
“We are grateful to the support shown by both Hastings Borough Council and the Hastings Town Deal programme as we collectively look to regenerate Hastings Town Centre post pandemic.”
Cllr Paul Barnett, lead for Regeneration at Hastings Borough Council, added: “We are delighted to hear that this unit has new tenants so quickly following New Look’s departure. Subject to final Town Deal business case approval, the introduction of an additional temporary Job Centre into Priory Meadow will mean people from across the town can easily access the support needed to get them into work or into a new sector.
“Combined with the introduction of a new health and fitness facility this really begins to address the ambitions in the Town Deal Investment Plan to diversify our town centre into somewhere people want to come to for more than just the shops.
“We look forward to seeing our town centre continuing to evolve through the programme, which is set to bring in over £24m of Town Deal funding and a further £85m of additional funding”.