Completion day is when ownership of the business formally transfers. For both buyer and seller, it is the culmination of weeks or months of preparation — and the start of the transition. Getting the practicalities right on the day, and in the days immediately following, makes the difference between a smooth handover and a chaotic one.
Quick Answer
On completion day, legal documents are executed, the purchase price is transferred, and ownership passes from seller to buyer. In most SME transactions, completion takes place simultaneously with exchange — meaning contracts are signed and money moves on the same day. The days immediately after completion involve a series of practical handover steps that should be planned in advance.
Contents
What happens on completion day
Completion is the legal moment when ownership of the business transfers. In a share sale, this means the shares are transferred from seller to buyer and the buyer becomes the legal owner of the company. In an asset sale, the specified assets transfer to the buyer and the seller's company ceases to own them.
For most SME transactions, completion is simultaneous with exchange — there is no gap between contracts being signed and ownership transferring. Both parties sign the documents, funds are confirmed, and the deal is done.
The mechanics of completion are coordinated by the solicitors on both sides. In practice, most of completion happens via email and phone, with physical attendance at a solicitor's office less common than it once was.
What completion does not immediately resolve is the practical handover: keys, passwords, introductions, systems access, staff briefings, and the many operational tasks that must happen in the hours and days that follow. These should be planned well before completion day itself.
Legal documents at completion
The exact documents depend on whether the deal is a share sale or asset sale, but typically include some or all of the following.
Share sale completion documents
Signed Share Purchase Agreement (SPA):The main contract, signed by seller and buyer
Stock transfer form(s):The legal instrument that transfers the shares — signed by the seller and delivered to the buyer
Board minutes:Approving the transfer, registering the new shareholder, changing directors and bank signatories
Resignation letters:From any directors or company officers who are leaving on completion
Appointment letters:For any new directors being appointed at completion
Disclosure letter:Signed by the seller, disclosing known matters that qualify the warranties in the SPA
Tax deed:A separate indemnity covering specific tax risks (common in transactions with significant tax exposure)
Service agreement or consultancy agreement:If the seller is staying on post-completion in an employed or consultant capacity
Restrictive covenant deed:Sometimes a standalone document; often within the SPA
Asset sale completion documents
Business Purchase Agreement (BPA) or Asset Purchase Agreement (APA):The main contract
Bill of sale or asset schedule:A detailed list of all assets transferred
Assignment or novation documents:For key contracts, intellectual property and domain names
Lease assignment deed:Transferring the lease to the buyer (with landlord consent already obtained)
TUPE notifications:Confirmation that staff transfer information was provided to employees
Goodwill assignment:Formal assignment of business name, goodwill and trading style
Restrictive covenant deed:From the seller
Payment and funds transfer
How payment works
The buyer's solicitor holds the completion funds on their client account before completion. On completion, they release the funds to the seller's solicitor's client account. Once the seller's solicitor confirms receipt, they confirm completion and the legal documents take effect.
For deals with a portion of deferred consideration or an earn-out, the completion payment is only the upfront tranche. The deferred amounts are paid according to the schedule or milestones agreed in the sale agreement.
Verification of funds
Do not assume funds have arrived until your solicitor has confirmed cleared funds in their account. Do not hand over keys, passwords or business control until your solicitor has confirmed receipt of the completion amount. This is especially important for sellers.
Buyer's bank — notification
The buyer should notify their bank in advance that a significant incoming transfer is expected on completion day. Receiving a large unexpected payment into a business account can trigger fraud alerts and temporary holds. Speak to your business bank manager before completion to ensure the funds clear smoothly.
Seller's funds — receiving payment
The seller's solicitor will typically retain funds to cover their own fees and any amounts required to settle charges or discharge loans. Net proceeds are then transferred to the seller. Sellers should plan for funds to arrive a day or two after completion rather than the same day.
What completes on the day — a checklist
These are the items that should be resolved or confirmed on or immediately before completion day:
Legal:
All documents signed and exchanged between solicitors
Stock transfer form signed and delivered (share sale)
Seller's solicitor confirms funds received before handing over control
New director appointments confirmed (share sale)
Outgoing director resignations confirmed
Financial:
Completion funds confirmed as cleared in seller's solicitor's account
Working capital in the business confirmed at agreed level (if applicable)
Cash and bank balance agreed and reconciled
Director loan accounts resolved (repaid or written off as agreed)
Assets:
Physical assets on the agreed asset list confirmed as present and in agreed condition
Vehicle logbooks (V5Cs) signed and handed over
Keys, access cards, alarm codes handed over
Stock counted (if applicable) and agreed
Systems and digital:
All passwords and login credentials transferred (see below)
Website, domain and email hosting access transferred
Social media account access transferred
Online marketplaces (Amazon, eBay, Etsy etc.) account access transferred
POS and EPOS systems access confirmed
Cloud software and accounting system access transferred
Lease:
Lease assignment completed and registered (if not done before completion)
Landlord notified in writing of change of occupier
Rent deposit (if applicable) transferred or new deposit paid
Asset and systems handover
The practical handover of assets, systems and credentials is one of the most under-planned aspects of business completion. It is worth preparing a complete handover document well before completion day so that nothing is forgotten in the rush.
Physical assets
Walk through the premises with the seller on or before completion and physically verify all items on the asset schedule. Check the condition of key equipment. Ensure all keys, access fobs, security codes and safe combinations are handed over.
If the business has vehicles, the V5C logbook must be signed by the seller as the registered keeper and sent to the DVLA to transfer registration to the new owner. The buyer should also notify their insurance provider.
Digital systems and credentials
Create a comprehensive list of every digital asset, platform and system the business uses, and ensure full login credentials are transferred. This should include:
Business email account(s) — hosting provider, admin credentials, all existing addresses
Website and CMS (WordPress, Shopify, Wix, custom — admin login, hosting account, FTP details)
Domain registrar account (GoDaddy, Namecheap, 123-reg etc.) — confirm domain ownership transfers
Google Workspace or Microsoft 365 — admin credentials
Accounting software (Xero, QuickBooks, Sage) — admin access
CRM or customer database — admin credentials and data export
Social media accounts — Facebook, Instagram, LinkedIn, Twitter/X, TikTok — admin or ownership transfer
Google Business Profile — add buyer as owner, remove seller
Online marketplaces — Amazon Seller Central, eBay business account etc.
Point of sale / EPOS system — admin credentials and historic sales data
Banking and payment systems — PayPal, Stripe, card terminals
HMRC online services — the seller needs to transfer relevant HMRC account access
This list should be prepared by the seller at least two weeks before completion and verified by the buyer during due diligence.
Software licences
Where the business uses software under licences registered in the seller's name or the selling company's name, the buyer should confirm before completion that those licences are transferable and are transferred. Some software is licensed per user or per entity — the buyer may need to purchase new licences.
Staff on completion day
Informing staff
Staff should be informed of the change of ownership on or before completion day. In an asset sale, where TUPE applies, the obligation to inform and consult employees should have been fulfilled before completion. In a share sale, there is no strict legal obligation to inform employees on completion day, but it is good practice.
How you tell staff matters. A thoughtful, direct communication from both the outgoing and incoming owner — explaining what is happening, what will change and what will stay the same — sets the tone for the transition. Uncertainty and rumour are more unsettling for staff than honest communication.
Consider:
Whether to inform staff before or after completion (before is better if confidentiality can be maintained)
Whether the seller will be present to introduce the buyer to the team
How to handle questions staff may have about job security, terms and the future
Key personnel
Where key members of staff are essential to continuity — the head chef, the lead technician, the account manager with the most important client relationships — the buyer should have a plan for retaining and engaging them from day one. Consider whether retention bonuses or confirmed employment terms are appropriate.
Payroll
If completion falls mid-month, establish clearly which party is responsible for the payroll run for the period including completion. In most deals, the seller pays up to completion and the buyer takes over from the day after. Ensure the payroll provider is notified of the change.
Customer and supplier notifications
When to notify
Customers and suppliers should typically be notified on or shortly after completion day — not before. Pre-completion notifications risk the deal becoming known before it is concluded and could unsettle relationships.
How to communicate
The most effective approach is a joint communication from both the seller and the buyer — one that reassures customers that service continuity is the priority, introduces the new owner, and invites any questions. The outgoing owner's endorsement of the new owner carries significant weight with long-standing customers.
For key customer relationships, a personal call from the seller (introducing the buyer) is far more effective than a letter or email.
What to include in notifications
Brief explanation of the ownership change
Assurance of continuity of service, team and contact details
Introduction of the new owner
Updated contact details if anything is changing (email address, bank account for payments)
Any relevant operational changes
Supplier notifications
Suppliers need to know who to invoice and where to send delivery documentation. Update supplier records with the new company name, address (if applicable) and bank payment details. If the deal is an asset sale, suppliers may need to enter into new contracts with the buyer's entity.
Bank accounts and financial transition
Buyer's business bank account
The buyer needs a business bank account in their own name (or the acquired company's name) before completion. If acquiring a company via share sale, the existing company bank account continues — the buyer needs to be added as a signatory and the seller removed. This requires the bank's cooperation and typically takes several days.
Contact the bank before completion day. Do not assume you can change signatories instantly on the day.
Seller's access removed
In a share sale, the seller's bank access should be removed promptly after completion. Outstanding authority to transact on the company's account after ownership has transferred creates risk for both parties.
VAT account
If the business is VAT registered, the buyer (in an asset sale) may need their own VAT registration — or may take over the seller's VAT number if TOGC conditions are met and agreed. In a share sale, the company's VAT number continues unchanged. Notify HMRC of changes to company officers and address.
Deferred consideration
Where part of the price is deferred, set up the payment schedule immediately after completion. Both parties should have a clear written schedule agreed in the sale agreement, with bank details confirmed. Disputes about deferred payments are common — clear documentation reduces the risk.
HMRC and Companies House notifications
Share sale — Companies House
After a share sale, the new shareholder and director details must be filed at Companies House:
Change of director:Form AP01 (appointment) and TM01 (termination) — must be filed within 14 days
Change of shareholder:The confirmation statement (next annual filing) will reflect the new shareholder. The company register (held internally) should be updated immediately
Change of registered office (if applicable):Form AD01 — must be filed within 14 days
Asset sale — new company registration
If the buyer is purchasing through a new company, that company should be incorporated before completion (ideally several weeks before). Company formation takes 24–48 hours via Companies House; VAT registration takes several weeks. Do not leave these to the last minute.
HMRC notifications
PAYE:Notify HMRC of the change of employer (in an asset sale, a new PAYE scheme is needed for the buyer's entity)
VAT:Notify HMRC of change of ownership (share sale) or register for VAT (asset sale buyer, if not already registered)
Corporation tax:HMRC is notified of a new company when it is registered at Companies House; the company must then register for corporation tax and file returns
Other notifications
Depending on the sector, other notifications may be required:
The premises licence (alcohol, entertainment) — notify the local licensing authority
Food business registration — notify the local authority
Care/childcare — notify CQC or Ofsted as applicable
Transport / HGV operations — notify DVSA and update the operator licence
Financial services — notify the FCA of change of control
The week after completion
Completion day is the start of the handover — not the end of it. The following tasks typically need to happen within the first week:
Confirm payroll arrangements for the first pay period under new ownership
Update Companies House with director and officer changes
Notify HMRC of change of employer (PAYE) if asset sale
Open or update business bank account; remove seller's bank access
Notify key customers personally (phone calls for top accounts)
Notify key suppliers with new payment details
Update insurance — employers' liability, public liability, property, vehicle
Update any leased or financed equipment records
Transfer Google Business Profile management to new owner
Update website contact details, about page and any seller personal content
Check and update online directory listings (Yell, Thomson Local etc.)
Notify any relevant professional bodies or trade associations
Confirm that all digital credentials and system accesses are working
Handover period — managing the transition
Most business sales include an agreed handover period — a number of weeks or months during which the seller remains available (as an employee, consultant or simply on a goodwill basis) to support the transition.
A typical handover period for an SME is two to eight weeks. For businesses where the owner is central to customer relationships or technical knowledge, a longer period — three to six months — may be agreed.
What makes a good handover
Structured plan:Both parties agree in advance what the seller will do during the handover, what they will introduce the buyer to, and what outcomes the period is designed to achieve
Customer introductions:The seller introduces the buyer personally to key customers — by phone, email or in person
Supplier introductions:The seller introduces the buyer to key suppliers and explains any existing relationship nuances
Operational knowledge transfer:The seller walks the buyer through operational processes, explains how things work, and identifies known issues or upcoming tasks
Staff introductions and context:The seller introduces the buyer to each staff member and shares context about their roles, strengths, and anything the buyer needs to know
Written handover notes:A written summary of key information — suppliers, customers, processes, logins, contracts, upcoming renewals — that the buyer can refer back to after the seller has left
Common handover problems
Seller disengages too quickly:The handover period ends before the buyer is comfortable. Plan for sufficient time and put it in the contract.
Seller overstays:Where the seller continues to make decisions or undermines the buyer's authority after completion, it creates confusion for staff and customers. The boundary between handover support and active management should be clear.
Key information not captured:Critical knowledge that exists only in the seller's head — supplier relationships, customer quirks, system workarounds — must be systematically extracted during the handover.
Full completion checklist
Before completion day
All legal documents reviewed and approved by solicitors
Funds confirmed as ready to transfer
Working capital level agreed and confirmed
Asset schedule verified and agreed
Lease assignment confirmed with landlord (if asset sale)
TUPE notifications completed (if applicable)
Handover document prepared by seller (systems, credentials, contacts)
Bank notifications made — both parties
Payroll transition plan agreed
Completion day
All documents signed and exchanged
Funds received confirmed by seller's solicitor
Keys, access cards and alarm codes handed over
All digital credentials handed over and verified
Stock counted and agreed (if applicable)
Staff briefed
Seller confirmed off company bank account (or change in process)
Week one post-completion
Companies House filings made (share sale — directors/officers)
HMRC notified (PAYE, VAT as appropriate)
Insurance updated
Key customer personal notifications made
Supplier notifications sent with new payment details
Google Business Profile transferred
Website updated
Deferred payment schedule set up
Handover period
Structured handover plan agreed and signed off
Customer introductions completed
Supplier introductions completed
Written handover notes completed and signed off
Operational knowledge transfer signed off
Final handover meeting completed at end of period
FAQs
What happens if funds don't arrive on completion day?
If completion funds do not arrive as expected, completion does not occur — legally, the deal is not done. Your solicitor will manage the communication with the other side. In most cases, a short delay (same day or next morning) is resolved without issue. If funds are materially delayed or do not arrive, your solicitor will advise on your options under the sale agreement. Do not hand over control of the business until your solicitor confirms cleared funds.
Can completion happen remotely?
Yes. The vast majority of SME completions now happen remotely — documents are exchanged via email, funds are transferred electronically, and physical presence at a solicitor's office is rarely required. The practical handover (keys, credentials, on-site walk-through) usually happens in person at the business premises.
What if something is missing or broken on completion day?
If an asset listed in the sale agreement is missing or in materially worse condition than agreed, your solicitor should be notified immediately. You may be able to withhold a portion of the completion funds (via an escrow arrangement agreed in advance), require the seller to replace or repair, or claim against the seller's warranties after completion. Address this before releasing funds — recovering money after completion is harder.
How long does the handover period last?
Typically two to eight weeks for most SME transactions. Complex businesses, or those where the owner has personal customer relationships or specialist knowledge, may justify a longer period of three to six months. The handover period and its terms (whether it is paid, what the seller is expected to do) should be agreed in the sale agreement before completion.
Who tells the staff?
This depends on the deal structure and the timing agreed between the parties. In most deals, staff are told on or shortly before completion day — ideally by both the outgoing and incoming owner together. In asset sales with TUPE obligations, information must be given to employees before completion as part of the TUPE process.
Do I need to tell HMRC that the business has changed hands?
Yes — in various ways, depending on structure. In a share sale, the company remains the same but director and officer changes must be filed at Companies House. In an asset sale, the buyer needs new HMRC registrations (PAYE, VAT, corporation tax) in their own entity. Both situations require HMRC notification. Your accountant and solicitor will advise.
Key takeaways
Completion is the legal moment when ownership transfers — funds must be confirmed as received before control is handed over.
In most SME transactions, exchange and completion happen simultaneously — on the same day, with the same documents.
Legal documents at completion include the signed SPA or BPA, stock transfer forms (share sale), assignment and novation documents (asset sale), and board resolutions.
Practical handover — keys, credentials, systems access, staff briefings — must be planned in advance and executed promptly.
Staff should be informed on or shortly after completion day; key customers should receive personal contact from the seller introducing the buyer.
Companies House and HMRC must be notified of relevant changes within the required timeframes.
A structured handover period — agreed in the sale agreement — is essential for knowledge transfer, customer introductions and operational continuity.
Seek independent legal and accounting advice throughout the completion process.
Related resources
Important disclaimer
Buy a Business Ltd is a marketplace, not a broker. Information, guides, checklists and examples on this site are for general guidance only and do not constitute legal, tax, financial, investment, valuation, brokerage or regulated advice.
Completing a business sale involves significant legal and financial obligations. You should seek independent professional advice — from a qualified solicitor and accountant — throughout the completion process.
Sources and useful references
Companies House: Director and shareholder change filing guidance
GOV.UK: TUPE guidance for employers and employees
HMRC: PAYE and VAT change of ownership guidance
Solicitors Regulation Authority: SRA-regulated solicitor register
GOV.UK: Stamp duty on share transfers

