Buy a second home or a rental property anywhere in London and the stamp duty bill carries a flat 5% surcharge on top of the standard rate. Expressed as years of council tax at the local Band D charge, that surcharge alone runs from £19,125 in Barking and Dagenham to £59,000 in Kensington and Chelsea — but the borough-by-borough ranking of who pays the most relative to their council tax bill does not simply track house prices. It reorders at both ends of the table once the surcharge is added, because council tax bands and the stamp duty surcharge are set by entirely different mechanisms.
The cheap end flips first
On a straight home-mover's stamp duty bill, Barking and Dagenham is the cheapest of London's 33 boroughs to clear in years of council tax: a 2025 median sale price of £382,500 produces a stamp duty bill of £9,125, or 4.2 years of the borough's £2,198.51 Band D charge. Croydon, with a higher median price of £425,000, comes a close second on the mover calculation at 4.3 years.
Add the second-home surcharge and the order swaps. Croydon's bill rises to £32,500 — 12.5 years of council tax — while Barking and Dagenham's rises to £28,250, or 12.8 years. Croydon overtakes it as the cheapest borough in the capital to buy a second property in, purely because Croydon levies the highest Band D council tax of any London borough (£2,599.91), which shrinks the years-of-council-tax ratio even though the cash stamp duty bill is higher.
The expensive end flips too
The same mechanism plays out in reverse at the top of the table. On the mover calculation, Kensington and Chelsea is the most expensive borough by some distance: a £1,180,000 median price produces a £61,750 bill, or 37.1 years of its £1,666.65 Band D charge — well ahead of Westminster's 32.4 years on an £880,000 median.
Once the second-home surcharge applies, Westminster overtakes it. Westminster's bill rises to £78,000 (74.3 years of council tax); Kensington and Chelsea's rises to £120,750 (72.5 years) — a slightly smaller multiple, because Westminster charges the second-lowest Band D rate in London (£1,049.55, behind only Wandsworth) on a still-substantial median price. A lower council tax bill, not a lower stamp duty bill, is what pushes Westminster to the top.
The full 33-borough table
Every figure below is a 2025 median sale price (HM Land Registry, category A transactions, houses and flats, 84,850 sales across all 33 boroughs) run through the stamp duty calculator with the additional-property surcharge applied, divided by each borough's 2026-27 council tax Band D charge.
| Borough | 2025 median price | Band D 2026-27 | Stamp duty as a second home | Years of council tax |
|---|---|---|---|---|
| Croydon | £425,000 | £2,599.91 | £32,500 | 12.5 |
| Barking and Dagenham | £382,500 | £2,198.51 | £28,250 | 12.8 |
| Bexley | £430,000 | £2,366.36 | £33,000 | 13.9 |
| Havering | £450,988 | £2,424.66 | £35,099 | 14.5 |
| Sutton | £455,000 | £2,378.64 | £35,500 | 14.9 |
| Lewisham | £470,000 | £2,237.33 | £37,000 | 16.5 |
| Enfield | £480,000 | £2,267.67 | £38,000 | 16.8 |
| Greenwich | £460,000 | £2,107.86 | £36,000 | 17.1 |
| Kingston upon Thames | £550,000 | £2,609.20 | £45,000 | 17.2 |
| Hounslow | £485,000 | £2,185.56 | £38,500 | 17.6 |
| Redbridge | £510,000 | £2,294.58 | £41,000 | 17.9 |
| Harrow | £550,000 | £2,511.07 | £45,000 | 17.9 |
| Newham | £451,200 | £1,944.23 | £35,120 | 18.1 |
| Waltham Forest | £540,000 | £2,386.96 | £44,000 | 18.4 |
| Bromley | £525,000 | £2,140.04 | £42,500 | 19.9 |
| Hillingdon | £510,000 | £2,045.46 | £41,000 | 20.0 |
| Brent | £550,000 | £2,235.27 | £45,000 | 20.1 |
| Ealing | £533,475 | £2,138.53 | £43,348 | 20.3 |
| Haringey | £575,000 | £2,313.78 | £47,500 | 20.5 |
| Merton | £550,000 | £2,146.76 | £45,000 | 21.0 |
| Lambeth | £543,500 | £2,047.11 | £44,350 | 21.7 |
| Tower Hamlets | £500,000 | £1,837.78 | £40,000 | 21.8 |
| Southwark | £535,000 | £1,967.26 | £43,500 | 22.1 |
| Barnet | £580,000 | £2,132.60 | £48,000 | 22.5 |
| Hackney | £590,000 | £2,060.30 | £49,000 | 23.8 |
| Richmond upon Thames | £720,500 | £2,486.10 | £62,050 | 25.0 |
| Islington | £650,000 | £2,108.15 | £55,000 | 26.1 |
| Camden | £780,000 | £2,207.55 | £68,000 | 30.8 |
| Hammersmith and Fulham | £706,000 | £1,519.51 | £60,600 | 39.9 |
| Wandsworth | £650,000 | £1,028.21 | £55,000 | 53.5 |
| City of London | £820,000 | £1,329.56 | £72,000 | 54.2 |
| Kensington and Chelsea | £1,180,000 | £1,666.65 | £120,750 | 72.5 |
| Westminster | £880,000 | £1,049.55 | £78,000 | 74.3 |
Why the surcharge narrows the spread, not widens it
It might seem obvious that adding a flat 5% surcharge to every borough would stretch the gap between cheapest and priciest further apart. It does the opposite. On the mover-only calculation, the spread between Barking and Dagenham (4.2 years) and Kensington and Chelsea (37.1 years) is 8.9 times. Add the surcharge, and the spread between the new cheapest (Croydon, 12.5 years) and the new most expensive (Westminster, 74.3 years) narrows to 5.9 times.
The reason is that standard stamp duty is a tiered, progressive tax, while the surcharge is a flat 5% of the whole price. Barking and Dagenham's stamp duty bill more than triples once the surcharge is added (£9,125 to £28,250) because most of its £382,500 median sits in the untaxed or lightly-taxed lower bands under the standard schedule. Kensington and Chelsea's bill not quite doubles (£61,750 to £120,750), because a large share of its £1,180,000 median was already taxed at the higher standard rates before the surcharge was even applied. Cheaper boroughs see a bigger proportional jump, which pulls the bottom of the table up faster than the top — narrowing the ladder rather than stretching it. Council tax bands, set independently of house prices, then decide exactly where each borough lands within that narrower range.
Barking and Dagenham is also a useful anchor against the first-time buyer version of this calculation: a first-time buyer completing at the same £382,500 median pays £4,125 in stamp duty (1.9 years of council tax) thanks to first-time buyer relief. A second-home buyer at the identical price pays a £19,125 surcharge on top of the standard rate — more than four and a half times the first-time buyer's entire bill, before the standard-rate stamp duty is even counted.
Not every additional-property purchase is a landlord's
The 5% surcharge applies to anyone completing on a residential purchase while already owning another property — landlords buying to let, but also second-home buyers and people who complete on a new purchase before selling their previous main home. HMRC allows a refund of the surcharge if the previous main residence is sold within a set window after completion; buyers in that position can check current eligibility and deadlines with a conveyancer.
Try it on your own numbers
The stamp duty calculator lets you run any London price with the additional-property surcharge switched on, and the postcode tool breaks down the full cost of a property on a specific street, including its council tax band. For the equivalent figures without the surcharge, the home-mover version of this league table and the first-time buyer cut of the same 33 boroughs use the identical price ladder. For the mechanics behind why council tax and house prices move independently of each other across the capital, see our explainer on London's council-tax-versus-house-price inversion. More borough and market data is available in our market analysis section.
This is general information about how stamp duty and council tax are calculated, not advice on any individual purchase. Speak to a qualified adviser before acting.