How to Price a Boiler Installation
A boiler install quote is more than a boiler and a day's labour — get the components right and you protect your margin; miss the flue run, the system upgrade or the make-good and you carry the cost yourself.
Pricing a boiler installation well is the difference between a busy diary that pays and one that quietly loses money. The boiler itself is often the smallest variable; the labour, the flue and gas run, the system work, the controls and the make-good are where quotes diverge — and where under-pricing hides.
This guide breaks a full installation quote into its parts, gives indicative UK ranges to orient you, and shows how to build a figure from your own costs rather than a competitor's advert. Every install is notifiable work that must be carried out and commissioned by a Gas Safe registered engineer — the figures here are guidance, not fixed prices.
Key takeaways
- Price the whole job, not just the boiler — labour, flue and gas run, system upgrade, controls and make-good all belong in the quote.
- A straight combi swap sits at the lower end; a boiler-type conversion or a move to a new location sits well above it.
- Build the figure from your day rate and costs, then sense-check against local rates — never the other way round.
- A power flush or system clean, magnetic filter and new controls are common line items that customers expect to see itemised.
- Quote in writing with a clear scope so variations are priced changes, not arguments — and register and commission every install properly.
What goes into a boiler installation quote
A complete quote covers the appliance and its warranty registration, the labour to remove the old boiler and fit the new one, the flue kit and any extension, the gas supply (often an upgrade to 22 mm to feed a modern combi), condensate disposal, controls, a system clean and inhibitor, and the make-good afterwards. Leaving any of these out means absorbing the cost or arguing over an extra later.
The cleanest quotes itemise the significant elements so the customer sees what they are paying for, and so a change of scope on the day is a priced variation rather than a dispute. That transparency also separates you from a bare 'supply and fit' figure that hides what is actually included.
Indicative UK ranges
As a rough orientation for 2026, a straightforward like-for-like combi swap commonly falls in the region of a few days' work plus the appliance, while conversions and relocations run higher because of the extra pipework, flue and make-good. Treat the figures below as indicative bands that vary significantly by region, boiler brand and the state of the existing system — your price should come from your own costs.
| Job type | Indicative total (varies by region) |
|---|---|
| Like-for-like combi swap | £1,800–£3,000 |
| Regular/system to combi conversion | £2,800–£4,500+ |
| New system boiler with cylinder | £3,000–£5,000+ |
| Boiler relocation (new position) | add £400–£900+ |
Doing this on a job? Quotes — part of TradePlanr. Free to start, no card needed.
The cost drivers that move the figure
Region and travel move labour cost as much as the work itself, exactly as they do on a service. Beyond that, the biggest drivers are scope: a conversion between boiler types, moving the boiler to a new position, upsizing the gas supply, and the condition of the existing system all add time and materials.
The state of the current system matters more than most customers expect. A dirty system needs a power flush or thorough clean and a magnetic filter to protect the new appliance and its warranty; a system with the wrong controls needs those upgraded to meet current standards. Neither is optional if the install is to be done properly, so both belong in the quote from the start.
Protect the warranty in the quote
Manufacturers expect a clean system, inhibitor and often a filter as a condition of the guarantee. Pricing the clean and filter in from the start protects both the appliance and you — a warranty claim refused for a dirty system is an expensive lesson.
Building a price from your costs
Start from the day rate you actually need — covering wage, van, tools, insurance, registration, training and downtime — and multiply by a realistic number of days on site, including the strip-out, the pipework, the commissioning and the paperwork. Add the appliance, the flue and gas materials, the controls, the filter and inhibitor, and a sensible margin.
Doing this once with a day rate and job price calculator gives you a figure you can defend without reference to anyone else's advert. Then sense-check it against local rates: if the market sits well below your number, look at your efficiency and costs, not just your price.
Quote it cleanly, win it professionally
TradePlanr lets you build an itemised boiler-install quote, send it as a branded PDF the customer can accept, and roll it straight into the job, the Benchmark commissioning and the invoice — so the whole install runs from one record.
From guidance to action
Frequently asked questions
How much should I quote for a combi swap?
As an indicative 2026 range, a like-for-like combi swap commonly falls somewhere around £1,800–£3,000 including the appliance, with region, brand and system condition moving it. Build your own figure from your day rate, materials and a margin rather than copying an advert.
Should I include a power flush in a boiler quote?
Usually yes. Most manufacturers require a clean system and inhibitor, and often a magnetic filter, as a condition of the warranty. Pricing the clean or power flush and filter in from the start protects the new appliance and avoids a refused warranty claim later.
Why is a conversion more expensive than a swap?
Because converting between boiler types — or moving the boiler — adds pipework, a new flue route, controls and make-good, and often removal of a redundant cylinder or tanks. That extra time and materials is real work that belongs in the quote.
Do I need to itemise the quote?
It is good practice. Itemising the boiler, labour, flue and gas work, system clean, filter and controls shows the customer what they are paying for and turns a change of scope on the day into a priced variation rather than a dispute.
Related guides
How Much to Charge for a Boiler Service (UK 2026)
What gas engineers charge for a boiler service in 2026, how to work out your own price, and how to protect your margin.
Gas Engineer Day Rates UK
Indicative 2026 UK day-rate ranges and how to calculate the rate your own gas business actually needs to charge.
Combi vs System vs Regular Boiler
How the three boiler types differ, which suits which property, and what each means for the installation.
