Dexus is looking to offload the North Sydney tower that houses the NBN headquarters, in a sale expected to net north of $800 million.

100 Mount St is a 36-storey office and retail building, with five levels of underground parking for 113 cars.

The 41,900sqm building is primarily leased by NBN, who leases 20,364sqm, sub-leasing a portion to Hollard Insurance.

NBN has been in the building since 2016, and is unlikely to move.

North Sydney is in the middle of a tower boom, driven by the forthcoming Victoria Cross metro station, which will have a $1.4 billion tower build above it.

Stockland is also planning a $1.5 billion office tower in North Sydney, and is currently searching for a capital partner.

The sale of 100 Mount Street will set an anchor for the price of these towers. Last December, Dexus’ 50 per cent stake in the tower was independently valued at $445 million.