Move
Total: £71,615
- SDLT (HMRC)
- £41,750
- Estate-agent fee
- £9,165
- Survey
- £1,500
- Legal (sale + purchase)
- £2,500
- Removals
- £2,000
- Chain contingency (1.5%)
- £14,700
For homeowners in Hackney (London Borough of Hackney). Updated 2026-06-11.
Inner east London. Substantial Georgian (De Beauvoir), Victorian (Stoke Newington, Dalston, London Fields, Hackney Central) and Edwardian (Clapton) terrace stock — the highest density of period property in inner east London. Side returns extremely common; the local typical terrace has an outrigger and L-shape side alley. Significant Article 4 restrictions on many of those streets.
The borough covers the E1, E2, E5, E8, E9, EC2A, N1, N4, N16 postcode districts. Terraced homes here trade around £825,000 against the borough-wide £611,000 average.
In Hackney, the average home is valued at £611,000. Moving up by 60% to a £980,000 property triggers approximately £41,750 in Stamp Duty Land Tax (SDLT). By contrast, a 12 m² high-spec side return extension here costs around £82,524 all-in. The average home here is around £611,000 (ONS, 2026).
Adjust the inputs to see your scenario. The page updates instantly as you adjust the inputs.
Moving is £10,909 cheaper than extending
Total: £71,615
Side return extension — high spec
Total: £82,524
An extension of this type and size could add roughly £79,430 (≈13%) to your home's value — Nationwide Building Society, October 2025.
Where moving starts costing more than the extension you selected. The chart follows your inputs above.
Up to about £1,076,000 of target price, moving is the cheaper route in Hackney; beyond that line, extending wins.
Decision speed: MHCLG householder statistics, year ending September 2025, excluding agreed extensions of time.
HMRC bands applied to a £980,000 purchase — the default Hackney trade-up.
| Price band | Rate | SDLT due |
|---|---|---|
| £0 – £125,000 | 0% | £0 |
| £125,000 – £250,000 | 2% | £2,500 |
| £250,000 – £925,000 | 5% | £33,750 |
| £925,000 – £1,500,000 | 10% | £5,500 |
High specification at typical size, inner London rates, all-in.
| Extension type | All-in cost | vs moving |
|---|---|---|
| Side return extension (12 m²) | £82,524 | £10,909 more than moving |
| Rear extension (single storey) (22 m²) | £124,982 | £53,367 more than moving |
| Wrap-around extension (25 m²) | £108,388 | £36,773 more than moving |
| Kitchen extension (22 m²) | £124,982 | £53,367 more than moving |
| Loft conversion (dormer) (18 m²) | £47,093 | saves £24,522 vs moving |
| Loft conversion (mansard) (30 m²) | £103,155 | £31,540 more than moving |
"An architect-designed house extension in London may cost between £3,000 and £5,000 per square metre. Elsewhere in the UK, you can expect to pay between £2,000 and £3,500 per square metre."
Nearby by average property value — useful if you're weighing a move to an adjacent price tier. A comparable trade-up in Lambeth would carry about £42,250 of stamp duty — £500 more than in Hackney.
Stamp Duty Land Tax is calculated from the HMRC bands in force for the 2025–26 tax year. Verify any figure against HMRC's official calculator before committing. Extension costs use inner London £/m² rates by extension type — industry-estimate midpoints, presented as approximations.