Some of Sydney’s top corporate addresses, including Salesforce Tower overlooking Circular Quay and the home of JPMorgan on Castlereagh Street, could tumble in value by 15 per cent to 20 per cent, wiping off hundreds of millions of dollars, as office values endure a savage reset, according to Barrenjoey analysts.

Their analysis paints one of the bleakest outlooks yet for the local office market, warning that valuations here significantly lag what is happening abroad – where office towers have already been marked down heavily.