When a builder, plumber, or any other trader gives you a price for work, that price is either a quote or an estimate, and the difference between the two is far more significant than most homeowners realise. Getting this wrong can leave you legally exposed or facing a bill that is hundreds or even thousands of pounds higher than you expected.

What Is a Quote?

A quote (also called a quotation) is a fixed, binding offer to carry out specific work for a stated price. Once you accept it, the trader is contractually obliged to complete that work for the agreed sum, and getting both the quote and your acceptance in writing makes that easy to prove.1 They cannot charge more unless:

  • You change the scope of work (a “variation”)
  • Hidden problems come to light (for example, rotten joists once floorboards are lifted), the trader tells you extra work is needed, and you agree to pay for it1
  • The quoted price contained a genuine, obvious mistake of the kind most people would spot2

A rise in the trader’s own costs after quoting is not, on its own, a reason to charge more.2 In practice, reputable traders will document any variation before the extra cost is incurred, ideally with a written change order you both sign.

What Is an Estimate?

An estimate is an approximate indication of likely cost. It is not a fixed price. The final bill can, and often does, differ from the estimate, sometimes substantially. Under the Consumer Rights Act 2015, anything a trader says or writes about the service that you take into account when deciding to go ahead becomes a term of the contract, which is one reason a quoted price binds them.3 Where the contract fixes no price, the Act implies that you must pay a reasonable price for the service, and no more.4 Where only an estimate has been given, the final charge should still be reasonable, judged against the estimate and any changes along the way, but there is no hard ceiling.2

The word “estimate” should set off a mental alarm: ask the trader to clarify the basis, what contingencies they have allowed for, and how variations will be handled.

Key Differences at a Glance

FeatureQuoteEstimate
Binding on the trader?Yes, once acceptedNo
Can the price increase?Only via agreed variationsYes, within reason
Best forWell-defined, measurable jobsComplex or exploratory work
Typical documentFormal quotation letter / breakdownEmail or verbal figure
Your protectionHigh, Consumer Rights Act 2015Moderate, final charge must be “reasonable”
When to ask for itNew extension, kitchen, bathroom, roof replacementStrip-out, investigation works, major structural repairs

When You Will Get an Estimate Rather Than a Quote

Trades will usually only offer an estimate when the full scope genuinely cannot be known upfront:

  • Damp investigation and repair: the extent of damage behind plaster cannot be known until the plaster is off.
  • Drainage repairs: CCTV surveys may reveal more problems than expected.
  • Rewiring older properties: the condition of existing wiring and the number of remediation points cannot always be seen.
  • Underpinning: the depth and extent of foundation failure is uncertain until excavation begins.

In these cases, ask the trader to break the estimate into a fixed-price phase (the investigation) and a second quotation once the full scope is clear. This is standard practice on well-run jobs.

How to Get a Proper Quote

  1. Define the scope precisely before approaching traders. Vague briefs produce vague prices. Provide drawings, specifications, or at minimum a detailed written brief.
  2. Request quotes from at least three traders. Citizens Advice suggests getting written quotes from at least three before choosing; comparing them gives you a market benchmark and uncovers wildly high or low outliers.1
  3. Ask explicitly: is this a quote or an estimate? If they say quote, ask whether it is fixed or subject to any caveats.
  4. Insist on a written breakdown. A single lump sum offers no protection if a dispute arises. A good quote will separate labour, materials, plant hire, and any allowances or provisional sums.
  5. Understand provisional sums. A provisional sum is a budget allowance for an item whose cost cannot yet be fixed (for example, floor tiles chosen by the client). These are expected to change and are not binding.
  6. Do not read a prime cost sum as the price of the item. A PC sum is a supply-only allowance and nothing more. RICS defines it as excluding “all costs associated with fixing or installation, all ancillary and sundry materials and goods required for the fixing or installation”, the subcontractor’s design, preliminaries, overheads and profit, and the main contractor’s design, preliminaries, overheads and profit on top of that.5 Run a £5,000 PC sum for kitchen units through the main contractor’s share alone, at illustrative rates of 11% preliminaries and 2.5% overheads and profit, and it reaches the account at about £5,689, which is 13.8% more before a single hour of fitting. Taking the PC sums out of a quotation and calling them the cost of the kitchen understates it every time. Our note on why a published building rate is not what you pay walks the same additions in full.
  7. Agree how variations will be managed. A contract should state that no extra work is to be instructed without a written variation order signed by both parties before the work begins.

Typical Cost Ranges for Common UK Renovation Jobs (2026)

JobTypical Quote Range
Kitchen supply and fit (mid-range)£8,000 – £20,000
Bathroom refurbishment£4,000 – £12,000
Single-storey rear extension (per m²)£2,200 – £3,500/m²
Loft conversion (dormer, London)£55,000 – £90,000
Full rewire (3-bed semi)£4,500 – £8,000
New boiler supply and installation£2,200 – £4,500

These are illustrative ranges. Your actual quote will depend on specification, location, and site conditions.

Red Flags to Watch For

  • A trader who gives you a quote verbally only and refuses to put it in writing.
  • A quote with no breakdown, just a total figure.
  • Prices that are dramatically below the market range (often a sign the trader will seek to recover margin through variations).
  • No mention of how variations will be priced or approved.
  • Pressure to sign quickly or start before you have read the documents carefully.

What the Law Says

Under the Consumer Rights Act 2015, services must be performed with reasonable care and skill and at a reasonable price if no price was agreed in advance.6 The Act also gives consumers the right to require repeat performance of substandard work.7 If a fixed quote was agreed and the trader charges more without a good reason, such as extra work you agreed to, you are entitled to pay the quoted price only.2

For B2B contracts, where you are buying as a business rather than a consumer, the Consumer Rights Act does not apply and the implied terms come from the Supply of Goods and Services Act 1982, which covers both the materials supplied under a work-and-materials contract and the work itself, alongside ordinary contract law.89 The fundamental principle, that a quote is an offer capable of acceptance, holds either way.

Getting the Best Outcome

The simplest protection is to treat every price you receive with equal suspicion until you understand whether it is fixed or approximate. Ask the question directly. Put everything in writing. And before work begins, make sure you have a signed document, however brief, that states the price, the scope, and what happens if the scope changes.

A trustworthy trader will have no problem providing this. One who pushes back or gets vague is telling you something important.

References (9)

Figures in this note were checked against the sources below on 30 September 2026. Superscript numbers in the text point to them. Every source the site cites, by topic.

  1. 1technicalfairCitizens Advice, guidance.RN-IED4GGCitizens Advice sets out six steps for a homeowner before work starts: check if you need permission or approval, find good traders, get quotes before deciding, check that you and your trader have insurance, get a written contract, and know what to do if there are problems. Advice applies to England, with separate versions for Northern Ireland, Scotland and Wales. It names the professional registers to search: a planning consultant on the Royal Town Planning Institute website, a surveyor on the RICS website and an architect on the Architects Registration Board website. Warns that without the permission or approval needed you might be fined, prosecuted, made to put things right or undo the work, and may have problems selling later. Confirms planning permission is usually needed to build something new such as an annexe, to make a major change such as an extension, or to change the use of a building.
  2. 2technicalfairCitizens Advice, guidance.RN-K22APCCitizens Advice guidance for England on what to do when work at home goes wrong. Says the problem must be taken up with the trader who arranged the work even if they subcontracted all or part of it, and to gather paperwork and receipts, take photographs as evidence and note dates and times first. Where the job is poor, it explains that the Consumer Rights Act 2015 requires reasonable care and skill and gives the consumer the right to ask the trader to fix the problem where goods were supplied with the service, or to get a refund and stop the trader doing more work where only a service was supplied. Provides wording a homeowner can use when complaining, suggests asking for money off for inconvenience such as 5% of the cost as a goodwill gesture, and states the trader should fix the problem within a reasonable time and at no extra charge.
  3. 3technicalvery strongThe National Archives (legislation.gov.uk), legislation.RN-EQVKC0Section 50(1) treats anything said or written to the consumer by or on behalf of the trader about the trader or the service as a term of the contract, if the consumer took it into account when deciding to enter into the contract or when making any later decision about the service. Section 50(2) subjects that to anything said on the same occasion that qualified it, and to any change expressly agreed. Section 50(3) treats information provided under regulations 9, 10 or 13 of the Consumer Contracts (Information, Cancellation and Additional Charges) Regulations 2013 (SI 2013/3134) as contract terms, and section 50(4) makes any change to that information ineffective unless expressly agreed. This is the basis for holding a builder to a verbal promise, a written quotation figure or a stated completion date.
  4. 4technicalvery strongThe National Archives (legislation.gov.uk), legislation.RN-BXZ3F2Section 51 of the Consumer Rights Act 2015 governs the case where no price was ever fixed. It applies where (a) the consumer has not paid a price or other consideration, (b) the contract does not expressly fix a price or say how it is to be fixed, and (c) nothing treated as included under section 50 fixes one either. Where all three apply, subsection (2) treats the contract as including a term that the consumer must pay a reasonable price and no more, and subsection (3) makes what is reasonable a question of fact. This is the provision a homeowner relies on when a trade started work on a handshake and later issued an inflated invoice: the invoice is not automatically the price.
  5. 5technicalstrongRoyal Institution of Chartered Surveyors, a standard.RN-K45EY4The rulebook behind every professional cost per square metre figure, and free to download as a PDF from RICS, which makes it directly citable rather than paraphrased. NRM 1 is issued by the RICS Quantity Surveying and Construction Professional Group as one of a suite of three (NRM 1 order of cost estimating and cost planning, NRM 2 detailed measurement for building works, NRM 3 order of cost estimating and elemental cost planning for building maintenance works), all reissued in October 2022 as practice information having been published in October 2021 as guidance notes, with no material change to content. NRM 1 covers quantification of building works for cost estimates and cost plans, and also how to quantify the items that are not measurable building work: preliminaries, overheads and profit, project team and design team fees, risk allowances, inflation, and other development and project costs. It sets out the floor area method for order of cost estimates and defines the terms a note should use precisely: cost per m2 of gross internal floor area (cost/m2 of GIFA) is the unit rate which, when multiplied by the gross internal floor area, gives the total building works estimate, and gross internal floor area (GIFA, also gross internal area or GIA) is defined in Appendix A with reference to the latest edition of the RICS Code of Measuring Practice. It also distinguishes GEA (gross external area) and NIA (net internal area). This is the source to cite for why a cost per m2 figure is meaningless without stating which area basis it uses.
  6. 6technicalvery strongThe National Archives (legislation.gov.uk), legislation.RN-F06Z1FSection 49(1), in Part 1 Chapter 4 of the Consumer Rights Act 2015, states that every contract to supply a service is to be treated as including a term that the trader must perform the service with reasonable care and skill. Section 49(2) directs the reader to section 54 for the consumer's rights when that implied term is breached. This is the single provision that makes poor workmanship by a builder a breach of contract without the homeowner having to prove anything was written down, and it cannot be excluded to the extent it would stop the section 54 to 56 remedies applying.
  7. 7technicalvery strongThe National Archives (legislation.gov.uk), legislation.RN-H89TBVSection 55(1) defines repeat performance as requiring the trader to perform the service again to the extent necessary to complete it in conformity with the contract. Section 55(2) requires the trader to provide it within a reasonable time and without significant inconvenience to the consumer, and to bear any necessary costs incurred in doing so, expressly including the cost of any labour or materials. Section 55(3) removes the right where completing performance in conformity with the contract is impossible. Section 55(4) says what counts as a reasonable time or significant inconvenience is judged by the nature of the service and the purpose for which it was to be performed. This is the legal answer to a builder who offers to come back but wants paying again for the return visit.
  8. 8technicalvery strongThe National Archives, guidance.RN-Q28KFXSection 13 of the 1982 Act implies, where the supplier acts in the course of a business, a term that the service is carried out with reasonable care and skill.
  9. 9technicalvery strongThe National Archives, guidance.RN-FEGNXISection 1 of the 1982 Act: a contract transferring goods is covered whether or not services are also provided, so the materials in a work-and-materials contract fall under it.

  1. Before you get work done on your home, Citizens Advice, accessed 30 September 2026. citizensadvice.org.uk

  2. Problem with building work, decorating or home improvements, Citizens Advice, accessed 30 September 2026. citizensadvice.org.uk

  3. Consumer Rights Act 2015, section 50, The National Archives, accessed 30 September 2026. legislation.gov.uk

  4. Consumer Rights Act 2015, section 51, The National Archives, accessed 30 September 2026. legislation.gov.uk

  5. RICS NRM 1: Order of cost estimating and cost planning for capital building works, 2nd edition, Royal Institution of Chartered Surveyors, accessed 11 September 2026. rics.org

  6. Consumer Rights Act 2015, section 49, The National Archives, accessed 30 September 2026. legislation.gov.uk

  7. Consumer Rights Act 2015, section 55, The National Archives, accessed 30 September 2026. legislation.gov.uk

  8. Supply of Goods and Services Act 1982, section 13, The National Archives, accessed 30 September 2026. legislation.gov.uk

  9. Supply of Goods and Services Act 1982, section 1, The National Archives, accessed 30 September 2026. legislation.gov.uk