The Department for Work and Pensions has moved its West Norfolk office into the main borough council building in Chapel Street, King's Lynn.
The move is part of a government initiative, One Public Estate, to make better use of public sector buildings to reduce running costs while maintaining services.
The layout of the ground floor of King's Court has been changed to accommodate six public counters for the DWP, a range of interview rooms and meeting rooms, as well as preserving self-service facilities for both the council and DWP clients.
Julia Nix, East Anglia district manager for the DWP, said: 'Moving into shared premises means that we can provide exemplar services while protecting the public purse.'
Kathy Mellish, the council's cabinet member for facilities, said the building was now home to the council and West Norfolk Health, West Norfolk Clinical Commissioning Group and the DWP, helping to cut costs.
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