Boiler replacement in Portsmouth
Realistic prices first, then a fixed quote from a Gas Safe registered Portsmouth installer.
What boiler suits a Portsmouth home?
Portsmouth is one of the most tightly built cities in the country, with long rows of terraced houses across Portsea Island and plenty of those split into flats. On the mainland side, 1930s semis are more common. Space is usually the deciding factor: a compact combi suits most terraces and flats, while bigger semis may need a cylinder. We help you choose, then arrange a fixed price.
Victorian and Edwardian terraces: Tightly packed streets mean most houses suit a wall-hung combi in the kitchen or a bedroom cupboard. Check the flue terminal will not sit too close to a neighbour's window or a narrow alley.
Converted houses and purpose-built flats: Many larger Southsea houses are split into flats, each with its own small combi. Flue routes through shared walls and any lease conditions need checking before a swap.
1930s semis on the mainland side: A combi works for most three-bed semis. Where a second bathroom has been added, a system boiler and cylinder keeps hot water flowing to both.
Boiler replacement prices in Portsmouth
| Job | Typical price | Fitting time |
|---|---|---|
| Combi to combi swap | £2,200 to £3,400 | 1 day |
| System or regular to combi | £3,000 to £4,200 | 1 to 2 days |
| System boiler replacement | £2,800 to £4,000 | 1 to 2 days |
| Boiler and full system flush | add £300 to £500 | same day |
Typical prices including VAT, checked October 2026. Your installer gives you a fixed price in writing before any work starts. More detail in our boiler replacement cost guide.
Thinking about a heat pump instead?
With the £7,500 grant, a heat pump can cost less than you think in a well-insulated Portsmouth home.
Is a heat pump right for you?Areas we cover around Portsmouth
- Southsea
- Fratton
- North End
- Copnor
- Milton
- Eastney
- Hilsea
- Cosham
- Drayton
- Farlington
Also nearby: Boiler replacement in Southampton, Boiler replacement in Brighton, Boiler replacement in Bournemouth
Boiler replacement in Portsmouth: questions
How much is a boiler replacement in Portsmouth?
Swapping an old combi for a new one in Portsmouth generally costs £2,200 to £3,400 fitted, VAT included. Removing tanks and converting to a combi is usually £3,000 to £4,200. The quote you receive is fixed before the installer books you in.
I live in a converted flat. Can I replace my boiler?
Yes, in almost every case. Check your lease for anything about alterations, and let the installer see where the flue comes out. Flats in converted houses sometimes need a different flue route to meet current rules.
Will a new boiler fit where the old one is?
Usually. Modern combis are compact and often fit the same cupboard. If the old boiler was in an awkward spot, such as a cramped kitchen corner, many owners use the swap to move it somewhere more convenient.
Are the installers Gas Safe registered?
Yes. City Boiler connects Portsmouth homeowners only with Gas Safe registered installers, and we check before any quote. You can verify an engineer's ID number yourself on the Gas Safe Register website.