The £/sq ft Guide: Are London New Builds Overpriced? (2026)

You cannot tell whether a London flat is "expensive" by looking at its headline price. A £500,000 flat of 850 sq ft and a £500,000 flat of 1,200 sq ft are two entirely different products. The honest measure professionals use is the price per square foot (or per square metre). This guide explains London's real £/sq ft levels, how big the new-build premium actually is, and most importantly, how to run that check yourself with free data.

What Is £/sq ft in London?

According to analyses based on official data, in mid-2026 the average across London is roughly £7,500/m² (about £700/sq ft), and the median around £6,700/m² (about £620/sq ft). The median being lower than the average is because very high sales in prime central pull the average up; so the "typical" London property is closer to the median.

These averages hide the gulf between areas. Larger homes in outer London offer the lowest £/sq ft, while small, high-specification flats in prime central command the highest. The table below summarises typical levels (approximate; varies by area and property).

A note on context: London prices have fallen over the past year (roughly -2% annually on official data, more in some local analyses); this can strengthen a buyer's negotiating hand.

How Big Is the New-Build Premium Really?

Here we must be honest: the new-build premium is real, but there is no single correct figure for its size, and sources contradict each other. The reason is how the comparison is made. One analysis based on Land Registry data shows a headline price premium of ~23% across England and Wales, but that in London the headline premium looks much lower (~5%), while the premium per square foot is higher (~15%).

The reason for this inversion is critical: new builds in London are generally smaller than the older properties they are compared with. So the headline price looks similar, but you get less space; the real premium only appears when you look per square foot. Other analyses give higher figures; some find new-build flats in London are 30-45% more expensive per square metre than resale ones (especially in branded, riverside or transport-led developments). To sum up: the premium is real, but do not trust any single figure claiming "it is X%"; compare your own property against its own comparables on a per-square-foot basis. As a general rule, a premium above 30% warrants careful scrutiny.

What Justifies the Premium?

Part of the new-build premium can be justified by tangible benefits; it is not all "for nothing". The main justifications are: high energy efficiency (lower bills and a better EPC rating), typically a ten-year structural warranty (such as NHBC), very low maintenance/repair costs in the early years, included kitchen/bathroom/fixtures, and the ease of buying without a chain. If you will let it, a new property can be easier to rent and cause fewer problems.

There are also points to watch. A new-build price is usually the developer's "list" price, and the same premium may not hold on the resale market afterwards (so capital growth can be slower in the early years). Leasehold structures and ongoing costs like service charge and ground rent should also be examined carefully. And there is negotiating leverage: developers often offer incentives (a furniture package, a contribution to stamp duty or service charge); these can significantly lower the effective cost and should always be negotiated.

How to Run Your Own Check (Free)

This is the most valuable part of this guide: you do not have to trust a developer's or an agent's figure. You can run your own £/sq ft comparison with free data. The steps are simple:

This simple calculation turns "is this price reasonable?" from an emotional guess into an objective comparison, and strengthens your hand at the negotiating table.

Optivest Note: We must be honest here: Optivest is a property consultancy and also offers new-build projects in its portfolio. Precisely for that reason, encouraging you to run an independent check is the right thing to do: when assessing a property — from us or from anyone else — look not at the headline price but at £/sq ft, and run your own comparable check using Land Registry and EPC data. Optivest's investment consultancy service can help you do this analysis together, interpret local comparables and negotiate developer incentives. A good adviser is one who moves you towards the numbers, not away from them.

Important notice — not financial advice: This article contains general market information; £/sq ft figures are averages, change rapidly, and do not determine the value of an individual property. For a property's value, obtain an independent valuation (a RICS surveyor), and for investment decisions, consult an independent, regulated financial adviser (IFA). Optivest is not a licensed financial adviser.

Frequently Asked Questions

What is the average price per square foot in London?

As of mid-2026, the average across London is roughly £700/sq ft (~£7,500/m²) and the median around £620/sq ft (~£6,700/m²). Prime central luxury new builds reach £1,800-3,000/sq ft, and ultra-prime higher. Outer London is notably lower.

How big is the new-build premium?

The premium is real but there is no single figure; sources give figures ranging from 5% to 45% because the method of comparison differs. The critical nuance: in London the headline price premium can look low but is higher per square foot, because new builds tend to be smaller. Compare against your own comparables per square foot.

Is the new-build premium justified?

Part of it is: energy efficiency (lower bills), typically a ten-year structural warranty, low maintenance, included fixtures and a chain-free purchase. But premiums above 30% warrant careful scrutiny; and remember the service charge, ground rent and the fact that the premium may not hold on the resale market.

How do I calculate £/sq ft myself?

Take the internal floor area (m²) from the EPC, multiply by 10.764 to convert to sq ft, and divide the price by that area. Then get actual sales in the same area from HM Land Registry "price paid" data (free on gov.uk), do the same calculation for them, and compare. Both data sources are free.

Can you negotiate with a developer?

Yes. Developers often offer incentives (a furniture package, a contribution to stamp duty or service charge); these can lower the effective cost by thousands of pounds. Always negotiate incentives and include them in your value assessment, especially when the market is slow.

In Summary, and How to Reach Us

The headline price does not tell you whether a London property is expensive; £/sq ft does. London's median is around £620/sq ft and its average around £700/sq ft, and the new-build premium is real — but its size varies by method of comparison and becomes visible in London particularly on a per-square-foot basis. Your strongest tool is running your own free comparable check with Land Registry and EPC data.

Optivest also offers new-build projects; precisely for that reason we encourage an independent £/sq ft check and do this analysis together with you through our investment consultancy service (we are not a licensed financial adviser). Contact us or reach us on WhatsApp. See our investment consultancy service, our stamp duty calculator to test the costs, and our project listings for options.