Insight · May 2026
Why Do Builder Quotes Vary So Much?
Getting three builder quotes and finding they vary by 50%? This guide explains the 8 main reasons quotes differ and how to compare them fairly to find genuine value.
The 8 Main Reasons Builder Quotes Vary
- 1Different assumptions about what's included
One quote may include skips, materials, scaffolding and project management; another may include only labour. Always ask for a fully itemised breakdown.
- 2Different assessments of complexity
An experienced builder may spot a hidden complication (soft ground, old drainage, asbestos risk) that a less experienced one misses. The lower quote may not be cheaper once those issues surface.
- 3Different labour rates and overheads
A sole trader working from a van has lower overheads than a building company with premises and admin staff. Both can do excellent work — but their pricing structures differ.
- 4Different material specifications
One quote may spec standard materials; another may spec premium brands. Always compare material specifications before comparing prices.
- 5How busy the builder is
A builder with full order books for 6 months will price high. A builder with a gap in their schedule may price more keenly to fill it. Timing matters.
- 6Regional labour rates
London and the South East have labour rates 15–35% above the UK average. The same job in Manchester or the North East costs significantly less.
- 7VAT registration
VAT-registered builders must charge 20% VAT. Sole traders below the VAT threshold (£85,000/year) do not. Always check whether quotes are VAT inclusive.
- 8Risk allowance
Experienced builders include a contingency in their price for unforeseen issues. Cheap quotes with no contingency often lead to disputes and additional charges mid-project.
How to Compare Builder Quotes Fairly
Always Get at Least 3 Quotes
Three quotes give you enough data to identify an outlier. One unusually low quote usually means something has been missed or excluded. One unusually high quote may reflect a builder who doesn't want the job.
Ask for Itemised Breakdowns
A lump-sum quote tells you almost nothing. Ask each builder to itemise: materials, labour, plant hire, skips, scaffolding, project management, and any subcontractors.
Compare the Same Spec
Send each builder the same written specification. If you allow them to assume materials, you will get three quotes for three different jobs.
Check VAT and Payment Terms
Confirm whether each quote is VAT inclusive. Agree staged payment milestones — never pay more than 10–15% upfront to a builder you haven't worked with before.
Frequently Asked Questions
How much should builder quotes vary?
A 10–20% spread between three comparable builder quotes is normal. A spread of more than 30–40% usually means the quotes are not comparing the same scope of work, or one builder has missed something significant.
Should I always choose the cheapest builder?
No. The cheapest quote is most often cheap because something has been excluded, the materials are under-spec'd, or the builder has miscalculated. Choose the quote that offers the best value: fair price, clear scope, good reviews, and a proper contract.
Why do builder quotes take so long?
A thorough quote requires a site visit, measurements, material pricing from suppliers, and often input from subcontractors (plumbers, electricians). Allow 1–2 weeks for a detailed quote. Be wary of builders who quote from photos only.
What should a builder quote include?
A complete builder quote should include: itemised labour and materials, any groundwork or demolition, waste disposal, scaffolding if needed, contingency allowance, VAT status, payment schedule, start date, expected duration, and what is excluded.
Is a fixed-price quote better than a day-rate?
Fixed-price quotes give you cost certainty and protect against scope creep. Day-rate arrangements (typical for smaller jobs) can be appropriate when the scope is genuinely uncertain — but require careful monitoring. For any project over £5,000, always get a fixed price.
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