Extensions cost in Southampton
2026 prices for Hampshire · South East
Extensions in Southampton typically costs between £33,500 and £134,500, with most homeowners landing near £84,000. Local pricing sits about 12% above the UK average. Strong demand and overspill from London keep day rates high, though materials and waste costs are close to the national average.
£33,500 – £134,500
UK average £2,200 per m² · Southampton index 112
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Extensions prices in Southampton by finish level
| FINISH LEVEL | SOUTHAMPTON COST | WHAT'S INCLUDED |
|---|---|---|
| Budget | £33,500 – £50,500 | Entry-level materials, existing layout retained |
| Mid-range | £48,500 – £73,000 | Better fittings, some layout change |
| Premium | £65,500 – £98,500 | High-specification materials and full redesign |
£46,200
About 55% of a typical Southampton job, at South East day rates.
£37,800
Materials pricing is broadly national — this is where specification, not location, drives your total.
What affects extensions cost in Southampton
Victorian terraces in Portswood and Shirley with a large student and HMO market. Rewiring and bathroom refits are the highest-volume job types.
- Drainage runs needing diversion
- Party wall agreements with neighbours
- Poor ground conditions requiring deeper foundations
Rules in Southampton
Building control and planning applications for extensions work in Southampton go through Southampton City Council. Confirm before booking whether your property sits in a conservation area, is listed, or is covered by an Article 4 direction — each removes permitted development rights and changes the approval route.
Serving SO14, SO15, SO16, SO17 and the surrounding Hampshire area.
Find vetted trades near SouthamptonExtensions in Southampton: common questions
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