Property Law Online

Buying a home

Buying and selling at the same time

Two transactions, one handler, one completion day. Your sale and purchase run side by side and exchange within minutes of each other.

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Buying and selling at the same time is a purchase funded by a sale, with the two run in parallel so that both exchange together and complete on the same day. Property Law Online covers England and Wales and gives both files to one named handler on one combined fixed fee.

Why instruct us

  • Fee agreed in writing before we start
  • Covering England and Wales

Who needs a combined sale and purchase service?

A simultaneous move is two full transactions tied to a single date, usually with other households either side of you depending on it. The legal risk is not complexity. It is coordination, and the person best placed to manage it is the one who can see both files at once.

Home movers with a mortgage on both
Here the sale proceeds repay the old loan, the balance goes towards the new home and a new mortgage covers the rest. We manage the redemption, the new lender and the shortfall figure together.
Movers in a chain
Households above and below you are relying on your dates. We hold both your files, so when a link slips we know the same day and tell you what it means.
Downsizers
Selling a larger home to buy a smaller one, often with no new mortgage. The surplus is sent to you on completion once the sale money has funded the purchase.
Movers with a leasehold flat to sell
The management pack from your freeholder or managing agent is usually the slowest document on either file, so we order it on day one. See leasehold conveyancing.
Movers selling after a separation
Where one of you is selling the family home and buying alone, the sale, any transfer of equity and the purchase need to be sequenced. Removing a name after divorce covers the transfer side.
Not right for
Buying first and selling later with a bridging loan, or completing the two on different days by choice. Both are possible, and we act on them, but they are two separate transactions rather than a synchronised move.

What does buying and selling at the same time include?

One combined fixed fee covers both transactions from instruction to registration. Anything a particular property needs on top, such as a lease extension on the flat you are selling, is quoted before you instruct, never afterwards.

  • Your sale, in full

    Official copies obtained, TA6 and TA10 completed with you, contract pack issued, enquiries answered and your mortgage redeemed on completion. Everything on our selling a home page.

  • Your purchase, in full

    Title investigated, searches ordered on day one, enquiries raised, your lender's conditions met, land tax return filed and your ownership registered. Everything on our buying a home page.

  • One handler, one timeline

    The same person runs both files and you get one set of written updates covering both, so you see at a glance which side is waiting on what.

  • Synchronised exchange

    We do not exchange on your purchase before your sale. Both exchanges happen in one telephone sequence, minutes apart, with the same completion date written into both contracts.

  • The money mapped out early

    A single completion statement showing the sale proceeds, the redemption figure, the purchase price, the new mortgage advance, the land tax and any shortfall you need to fund, weeks before the day.

  • Chain management

    We speak directly to the conveyancers above and below you, agree target dates in writing where that helps, and escalate the moment a link goes quiet.

How does buying and selling at the same time work?

Both files run in parallel from the day you instruct. Neither waits for the other, but they arrive at the same two dates.

  1. Both files opened

    Identity checks once, not twice. Official copies of your title ordered, searches on the purchase ordered, and for any leasehold property the management pack requested the same day.

    Week 1

  2. Packs out and in

    Your contract pack goes to your buyer's conveyancer. Your seller's pack arrives and we read the title and the plan in full.

    Weeks 1 to 3

  3. Enquiries both ways

    We answer your buyer's enquiries and raise ours on the purchase. Search results come back and generate their own questions. Your new mortgage offer is issued and its conditions checked.

    Weeks 3 to 8

  4. Money confirmed

    Redemption statement obtained, purchase figures confirmed, and the completion statement sent to you showing exactly what you need to send us and when.

    Weeks 7 to 9

  5. Exchange on both

    Once the whole chain is ready, contracts are exchanged from the bottom up. Your sale exchanges, then your purchase, minutes later, with the same completion date in both.

    Weeks 9 to 12

  6. Completion on both

    Your buyer's money arrives, your old mortgage is redeemed, the balance goes straight out on the purchase with the new mortgage advance, and the keys are released to you. Land tax return filed and registration lodged.

    Weeks 10 to 14, then HM Land Registry processing

How does the mortgage work when buying and selling at the same time?

Two lenders are involved: the one being repaid on your sale and the one advancing money on your purchase. We deal with both, and the two figures decide how much of your own money you need on the day.

Redeeming the old mortgage
We obtain a redemption statement for the completion date, including any early repayment charge, and pay the lender from the sale proceeds before anything else goes out. Porting an existing deal to the new property is a lender decision; if you are porting, tell us and we align the two.
The new mortgage offer
The new lender instructs us to act for it. We satisfy its conditions, certify the title of the new home and request the advance for the completion date. The offer must still be valid on that date. Lenders publish different periods and, more easily missed, different starting points: Skipton Building Society publishes six months from the date of the first mortgage offer, while Coventry Building Society publishes six months from the date of application on cases submitted through its own platform, so part of that clock can have run before the offer exists. Nationwide publishes 180 days with an automatic 15 day grace period after expiry (all checked 20 September 2026). We read the expiry off your own offer and flag it early where it sits close to a long-stop date.
The shortfall
Where the purchase price plus land tax and costs exceeds the net sale proceeds plus the new advance, the difference comes from you. We confirm the figure early rather than in completion week.
The deposit
On exchange, the deposit from your buyer is normally passed up the chain and used as the deposit on your purchase, so you rarely need to find ten per cent in cash. Where your sale deposit is smaller than the one your seller wants, we agree the difference in advance.

Each lender may charge its own fees: an early repayment charge on the old loan, and arrangement or valuation fees on the new one. They are set by the lenders and appear on their paperwork, not on our quote.

What does it cost to sell and buy at the same time?

Property Law Online is not yet taking instructions, so there is no fee to quote today. This section explains how the cost of this work is usually made up.

A combined sale and purchase is quoted as one fixed fee before you instruct us, in writing, with our fee shown separately from the amounts paid to others on your behalf. Tell us whether either property is leasehold and whether there is a new mortgage, and we reply by email.

Usually covered by the professional fee

  • Sale: title, forms, contract pack, enquiries and redemption
  • Purchase: title, searches, enquiries and report
  • Acting for your new lender and satisfying its conditions
  • Synchronised exchange and same-day completion on both
  • Land tax return and HM Land Registry registration
  • One completion statement covering both transactions

Paid to others, passed on at cost

  • Search fees on the purchase, set by the local authority, water company and search providers
  • HM Land Registry fee on the purchase, set by the HM Land Registry fee order
  • Stamp Duty Land Tax or Land Transaction Tax on the purchase, where any is payable
  • The management pack on a leasehold sale, charged by the freeholder or managing agent
  • Bank transfer charges, one to redeem your mortgage, one to send the purchase money
  • Estate agent commission, paid from the sale proceeds if you ask us to

What can add to it: a leasehold property on either side, a new build purchase, a gifted deposit, a deed of trust between co-buyers, or a transfer of equity running alongside the sale. Each is quoted before you instruct, never afterwards.

How long does a chain transaction take?

Typically 8 to 12 weeks from accepted offers to completion where both properties are freehold, and 12 to 16 weeks where either is leasehold. Each additional link in the chain can add time. HM Land Registry then processes the registration of your new home; your ownership dates from completion.

What changes the timescale

  • The length of the chain and the speed of its slowest link
  • Whether either property is leasehold and how quickly the pack arrives
  • When your new mortgage offer is issued
  • How quickly the local authority returns the search on your purchase
  • Whether every party can agree on the same completion date
The stagesExample
  1. Both files opened
  2. Packs out and in
  3. Enquiries both waysIn progress
  4. Money confirmed
  5. Exchange on both
  6. Completion on both
An illustration of how a matter moves through these stages. We tell you when each one is done.

What goes wrong when buying and selling together?

  • Exchanging on the purchase before the sale

    If your purchase exchanges first and your buyer then withdraws, you are legally bound to buy with no money to buy with. Our practice is built to prevent it. Both exchanges are run in one sequence, sale first, purchase minutes later.

  • A shortfall discovered too late

    Estate agent commission, the early repayment charge, land tax and the search and registration fees all come off the top before the balance reaches your purchase. We send a completion statement weeks in advance so the figure you need to send is not a surprise.

  • The slowest link sets the pace

    A first-time buyer at the bottom of the chain waiting for a mortgage offer, or a leasehold management pack at the top, holds everyone. We escalate directly to the conveyancer concerned and, where it helps, get every party to commit to a target date in writing.

  • Higher-rate land tax charged by mistake

    If you complete the purchase before the sale, even by a day, you own two homes and the higher rates for additional dwellings apply, in England and in Wales alike. A refund is available if the old home is sold within three years, but the claim has a second and shorter deadline of its own: twelve months from the sale or from the filing date in England, whichever is later, and four years from the day after the filing date in Wales (Finance Act 2003 Schedule 4ZA paragraphs 3 and 8; Land Transaction Tax and Anti-avoidance of Devolved Taxes (Wales) Act 2017 Schedule 5 paragraph 8 and Tax Collection and Management (Wales) Act 2016 section 78, all checked 20 September 2026). A same-day move avoids the problem altogether.

Why do the sale and the purchase have to complete on the same day?

Because the money for the purchase comes from the sale. Your buyer's funds arrive with us, we pay off your existing mortgage, and the balance goes straight out to your seller's conveyancer together with your new mortgage advance. If the two days were different you would need somewhere to live, somewhere to put your belongings and a bridging loan for the gap.

The same logic applies to exchange. You cannot safely commit to buying until you are certain of selling, so the two exchanges happen together, and in a chain every exchange happens on the same afternoon from the bottom upwards. It also means the deposit your buyer pays on exchange is usually passed up the chain to serve as your deposit on the purchase, rather than you finding it in cash.

Your saleYour purchase
Week 1Title obtained, forms completed, pack issuedSearches ordered, seller's pack requested
Weeks 2 to 8Buyer's enquiries answeredOur enquiries raised, mortgage offer checked
Weeks 7 to 9Redemption statement obtainedReport to you, funds and deposit confirmed
Exchange dayExchanged first, completion date fixedExchanged minutes later, same date
Completion dayProceeds in, old mortgage redeemedBalance and new advance out, keys released

Can I break the chain by buying first?

Yes, if you can fund it. A bridging loan or a large amount of savings lets you complete the purchase before the sale, which removes the dependence on your buyer and can make your offer more attractive to a seller. The costs are the bridging interest and fees, and the higher rates of Stamp Duty Land Tax in England or Land Transaction Tax in Wales, because for a period you own two dwellings. The higher-rate tax can be reclaimed once the old home is sold, provided the sale happens within three years of the purchase, and the claim itself then has its own deadline, twelve months from the sale or the filing date in England, whichever is later, and four years from the day after the filing date in Wales. The extension where exceptional circumstances stopped the sale is narrow, and carries its own twelve month window to apply (Finance Act 2003 Schedule 4ZA paragraphs 3 and 8; Schedule 5 paragraph 8 of the Welsh Act and section 78 of the Tax Collection and Management (Wales) Act 2016, all checked 20 September 2026). Our Stamp Duty and LTT calculator shows the higher rates.

The other way to break a chain is to sell first and rent for a while. That makes you a chain-free buyer, which sellers and agents value, at the cost of two moves. We act on either route; what we do not recommend is completing the two on different days without a plan for the gap.

What if my buyer pulls out after I have found somewhere to buy?

Before exchange, nothing binds them and you cannot force the sale. What you keep is the work: your contract pack, your answered enquiries and your searches on the purchase all stand, and a replacement buyer starts from a much shorter position. Your seller may agree to wait, or may not; we tell them promptly and honestly so the decision is made with the facts.

Frequently asked questions

Should I use the same conveyancer for my sale and purchase?

Almost always yes. One firm holding both files can synchronise exchange and completion without waiting on another firm, sees both sets of enquiries, and knows the moment one side slips. You also go through identity checks only once.

What documents do I need to sell and buy at the same time?

Photo ID and proof of address, your mortgage account number for the redemption statement, planning and building regulations documents and certificates for the home you are selling, the new mortgage offer once issued, bank statements showing any savings you are adding, and both estate agents' details. We send one checklist covering both files.

Can I complete my sale and purchase on different days?

You can, but you need somewhere to live and somewhere to store your belongings in between, and funds to bridge the gap. Completing the purchase first also triggers the higher rates of land tax until the old home is sold. We recommend synchronising the two unless there is a specific reason not to.

What if my sale price is lower than my purchase price?

You fund the difference from savings or a larger mortgage. The gap is not just the difference in prices: land tax, the early repayment charge, agent commission and fees all come off the top. We confirm the exact shortfall early in the process, not in completion week.

Do I pay two sets of legal fees?

You pay for both pieces of work, as one combined fixed fee agreed in writing before work starts. Identity checks, correspondence and completion are done once rather than twice. Third-party costs such as searches and land tax apply to the purchase only.

How is the deposit handled in a chain?

On exchange your buyer pays a deposit to us. With everyone's agreement that deposit is passed up the chain and used as your deposit on the purchase, so you rarely need to find ten per cent in cash. If your seller insists on a full deposit and your buyer's is smaller, we agree the top-up in advance.

What happens on completion day when I am buying and selling?

Your buyer's money usually arrives mid-morning. We redeem your old mortgage and send the balance, with the new mortgage advance, to your seller's conveyancer. Once they confirm receipt, your keys are released. In a long chain this can be mid-afternoon, so removals are best booked with a flexible window.

What makes a combined sale and purchase cost more?

A leasehold property on either side, a new build purchase, a gifted deposit, a deed of trust between co-buyers, or a transfer of equity running alongside the sale. Each adds work, and each is quoted before you instruct rather than added at the end.

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