selling
Part exchange a house: how it works, what to expect and the alternatives
Part exchange a house against a new build: how builders' schemes work, the rules two builders state, the trade-offs and how it compares with selling.
- 4 min read
- Last reviewed 4 November 2026
- By Your Property Check team
Key answer
Part 1 of 7
How part exchange works
In a part exchange, a home builder agrees to buy your existing house as part of the deal for one of its new homes. The agreed value of your house is deducted from the price of the new build, so you do not need a separate buyer for your old home. It is a builder's scheme, not a government one: GOV.UK's "Selling a home" guide does not mention it, and the rules differ by builder. This page describes two schemes as the builders themselves state them on their websites, checked on 4 November 2026. Other builders will have different terms, and a scheme can be withdrawn or changed, so read the current terms for the home you want. General information, not advice.
Part 2 of 7
What two builders say about their own schemes
Bellway states that your current house must be at least 30% lower in value than the Bellway home you want to buy. It says two independent estate agents will value your property and it makes an offer based on an average, using the 4-week selling price. Its offers are valid for 48 hours, are subject to contract, and it reserves the right not to proceed if information emerges that materially affects the valuation. It says the offer is available on selected developments and plots only.
Persimmon states that offers are based on independent valuations and "may be slightly below open market value". It says your home must be worth no more than 70% of the new build, that you must own your current home and it needs to be in good condition, that leaseholds should have at least 80 years left, and that part exchange is not available for first-time buyers. It also says it covers the estate agency fees on your existing home, and that you still pay reservation fees and your own legal costs.
These are the builders' words at the time of checking, not a verdict on either. They show how schemes usually have a value limit, a valuation step, a time limit on the offer and a list of excluded homes.
Part 3 of 7
Part exchange, open market sale or cash offer
| Factor | Part exchange | Open market sale | Cash offer |
|---|---|---|---|
| Who buys | The builder | A buyer found through an agent or privately | An independent cash buyer |
| Price | Based on independent valuations, may be below open market value | Aims for the market price | Typically below open market value |
| Speed | Builders say it can be quicker and more certain | GOV.UK says selling takes about 5 months on average | Can be quicker, but no one can promise a date |
| Fees | Builder may cover agent fees. You pay your own legal costs | Agent and legal fees, set by your contract | Buyer sets their own terms. Check what you pay |
| Eligibility | Set by each scheme | Any property | Set by each buyer |
| Choice of new home | Only selected developments | Any home you can buy | Not applicable |
| Main risk | Offer may lapse or be adjusted after a survey | Chain delays or a buyer withdrawing | Lower price for the certainty |
Part 4 of 7
Is part exchange cheaper once agent fees are counted?
Nobody can say in general, because no official source gives a typical part exchange discount and we do not quote one. The sum is personal: compare the builder's offer, less any difference in the new home's price, against what an open market sale would realistically bring after agent and legal fees. GOV.UK says the agent's fee depends on your contract, including whether it has sole selling rights, so get quotes. Our guide to estate agent fees sets out the sourced figures, and our sale method comparison tool lets you enter your own numbers.
Get your own written valuations first. If the builder's offer sits close to those valuations, the convenience may be worth it. If it is well below, you will see the cost of certainty in pounds.
Part 5 of 7
Which homes are eligible?
Each scheme sets its own rules. The two we read mention a value limit against the new build, ownership of the home, its condition, the minimum years left on a lease, and the area. Bellway also says some properties may be excluded, such as ex-local authority leasehold apartments, and that older homes may need further surveys. Check the builder's current terms for your property and your buyer status before you plan around it.
Part 6 of 7
The risks to weigh
- Valuation changes. Builders say the offer can be revisited if a survey finds damp, subsidence or structural defects.
- Time limits. Offers are valid for a short period, so have your paperwork and mortgage questions ready.
- Limited choice. You can only move to the builder's homes that offer the scheme.
- New-build issues. If something goes wrong with a new home, complaints go to a different body from estate agents. The Property Ombudsman says that for new-build developments you should look at the New Homes Ombudsman register of developers.
- Costs that remain. You still pay legal costs and any reservation fees.
Part 7 of 7
Alternatives
If you need speed and the numbers do not suit part exchange, compare selling on the open market, a chain-break route, or a cash buyer. Our guides to selling a house quickly and how cash house buyers work set out each trade-off, and our guide to bridging loans and alternatives covers buying before you sell.
Our take
Compare the builder's offer with your own valuations
Our view: part exchange buys convenience, and you can read the price of that convenience in pounds. Builders say offers may sit below open market value and can change after a survey, and each scheme sets its own limits. The common mistake is accepting before getting written valuations to compare.
What Your Property Check adds: the sale method comparison sets auction, estate agent and cash buyer routes side by side on net proceeds and timescale, and the house value check gives a range from sold prices to measure an offer against.
Our opinion, drawn from the facts on this page: not advice and not a forecast. We earn from OfferCheck reports and from introducing sellers to cash buyers, so weigh it with that in mind (see our disclosure). We are not authorised or regulated by the FCA.
Questions, answered
Frequently asked questions
What is part exchange?
How much less do you get in part exchange?
Is part exchange cheaper once agent fees are counted?
Which homes are eligible?
What are the risks?
Where this comes from
Sources
- Bellway: Part Exchange
- Persimmon Homes: Part Exchange pros and cons
- GOV.UK: Selling a home
- GOV.UK: Selling a home, getting an estate agent
- The Property Ombudsman
Last reviewed 4 November 2026 by the Your Property Check team. This page is general information, not legal, tax or financial advice. For your own situation, speak to a conveyancing solicitor or another qualified professional.