How to compare window quotes

Getting three prices for the same job sounds simple, until the quotes land and no two are laid out the same way. One is a single figure scrawled on a compliment slip; another runs to four pages of specification. The headline numbers look miles apart, yet you have no idea whether you are comparing the same windows, the same glass or the same guarantee. This guide is the hub for everything on the site: work through it once and you will know exactly how to compare window quotes without being dazzled by the biggest discount or the smallest total.

Start by making every quote describe the same job

The single biggest mistake is comparing prices before the specifications match. Ask each installer to quote for an identical brief: the same number of windows, the same opening style (casement, tilt-and-turn, sash), the same frame material and colour, and the same glazing. If one quote is for A-rated glass and another for standard double glazing, the cheaper one is not really cheaper. Write your brief down and hand the same sheet to everyone, so the differences that remain are down to the company, not the job.

Break each quote into the same four blocks

However a quote is presented, it can be reduced to four parts: the product (frames and glass), the labour (removal, fitting and making good), the extras (scaffolding, building control, disposal) and the guarantee. Rewrite each quote into those four blocks and the real gaps appear. Our guide to what a window quote should include lists every line a proper quote spells out, so you can see at a glance which company has left something vague. If you are not sure what a term means, the jargon explained page decodes it in plain English.

Judge value, not just the total

Price matters, but it is only one column. A quote that is a few hundred pounds more but includes A-rated glazing, a longer insurance-backed guarantee and a firm fitting date can be far better value than the cheapest line on the page. Energy efficiency is part of that sum: according to the Energy Saving Trust, replacing single glazing with modern double glazing can meaningfully cut heat loss, so the running cost of the window matters as well as the sticker price. If you want to understand where your money actually goes, it helps to read up on what windows actually cost and how the pieces are priced, and to get to grips with energy ratings explained before you weigh one glass spec against another.

Check the company behind the number

A quote is only as good as the firm standing behind it. For each installer, confirm they are FENSA or Certass registered, that the guarantee is insurance-backed so it survives if the company does not, and that the price includes your building-regulations certificate. Our list of questions to ask window installers turns this into a script you can use on the phone, and the quote red flags guide shows the pressure tactics and vague pricing that should make you pause.

Get the right number of quotes, then decide

Three comparable quotes is the sweet spot for most homeowners — enough to spot an outlier without spending every evening with a salesperson at the kitchen table. Our guide on how many window quotes to get explains why. Once you have them lined up, run each one through the window quote checklist before you sign anything. If funding or spreading the cost is on your mind, you can also look at funded glazing quotes; any funding and contribution options are subject to eligibility and a home survey, so treat them as one more line to compare rather than a headline saving.

Then take the next step

Comparing well only pays off if you have good quotes to compare in the first place. Start with a free, no-obligation quote from a vetted installer who covers your postcode, then use the guides above to weigh it against anything else you gather.

Free Window Quote is a free quote-matching service, not an installer. All quotes are free and no-obligation.