Homes in SW1X sell for a median of £2,525,000 across 86 sales over two years (HM Land Registry), which is +122% against the Kensington and Chelsea median of £1,135,000. Set against the local average rent of £3,629 a month (ONS), that implies a 1.7% gross yield here versus 3.8% for Kensington and Chelsea as a whole.
Rents are published per district, not per postcode, so the yield above applies the Kensington and Chelsea average rent to SW1X prices. It's the right way to compare postcodes on entry price, but rents do vary street by street, and gross yield ignores costs, voids and mortgage interest.
SW1X averages tell you where to look, not whether one particular flat stacks up. Paste a listing and gemhome runs the actual numbers: yield, cash flow, the lender stress test, EPC work and what the public records say about that specific address.
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