Current boiler supply-and-install budgeting ranges with the safety and registration checks that matter.
Applies to: UK homes; fuel, boiler type and system changes vary. · Last checked: 4 October 2026
Key points
• Checkatrade’s March 2026 guide puts a like-for-like gas combi replacement commonly around £2,500–£4,000 supply and install.
• Its wider total range is much broader where boiler type and system work change.
• Gas work must be carried out by an appropriately Gas Safe registered engineer.
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Current market guide
Checkatrade’s March 2026 guide gives £2,500–£4,000 as a typical like-for-like gas combi replacement range. It lists boiler installation itself around £1,000–£2,000, while broader system changes can cost considerably more.
What changes the price
• Boiler type and output.
• Moving the boiler or flue.
• Gas pipe upgrades.
• Cylinder or controls changes.
• System cleaning and filters.
• Condensate routing and making good.
Safety and compliance
For gas work, use an appropriately registered Gas Safe engineer. GOV.UK also lists installing or replacing a heating system among work that can require Building Regulations approval, with competent-person schemes available for qualifying work.
Sources and methodology
Pricing figures are third-party UK market budgeting references, not BuildPair prices or guaranteed local quotes. Legal and safety points are linked to current official guidance. Check the current source and your project circumstances before acting.
Related BuildPair guides
BuildPair provides general information and signposting, not legal, structural, gas, electrical or building-control approval. Requirements and prices vary by location, property and scope.
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