Melbourne landmark 404 Collins Street will trade one insurance tenant for another when Suncorp makes the building its new Melbourne headquarters next year.

The current Axa headquarters will be taken over by Suncorp in the second quarter of next year when more than 900 staff are resettled in the prime CBD location.

The three-year lease includes 15,000 square metres of commercial space. Axa is scheduled to move to its new Docklands home in Melbourne's west next year.

Suncorp's Melbourne consolidation will merge the resources of three offices in and around the city. A planned redevelopment of the site by owner Industry Superannuation Property Trust has now been delayed.