An earn-out is the deferred portion of a UK M&A purchase price, payable to the seller(s) only if the business hits specified financial targets over 2-4 years after completion. Earn-outs typically cover 20-40% of total consideration. The most negotiated terms: the metric (revenue vs EBITDA vs gross profit), the targets, the seller''s control during the earn-out period, and what happens to the metric if the buyer changes the business.

Done well, earn-outs bridge a valuation gap and align incentives. Done badly, they trap the seller in a job they wanted to leave, with a financial outcome controlled by someone else.

Why earn-outs exist

Three reasons a buyer wants one:

1. Bridge a valuation gap

The seller thinks the business is worth £10M based on growth potential. The buyer is comfortable paying £6M based on current performance. An earn-out structures the gap: £6M at completion, £4M conditional on hitting growth targets.

2. Transfer performance risk

If the business misses the targets, the seller takes the loss — not the buyer. The buyer locks in their downside protection.

3. Keep the seller engaged

A seller with significant deferred consideration has a strong financial reason to stay involved post-sale, support the transition, and protect the relationships that came with the business.

Typical UK earn-out structures

The standard shapes:

Time-based with cliff payments

Earn-out paid in annual instalments — typically Year 1, Year 2, Year 3 — each contingent on hitting that year''s target.

Pro: structured, predictable.
Con: missing one year''s target can forfeit that whole tranche even if the next year overperforms.

Cumulative-with-catch-up

Each year''s payment can be made up in subsequent years if cumulative performance is on track.

Pro: lumpy years don''t kill the earn-out.
Con: more complex to administer.

Pure performance — no time limit

The earn-out is paid when (and if) cumulative performance hits a threshold, with no specific year-end deadlines.

Pro: closer to the seller''s economic reality.
Con: rare; buyers prefer structured deadlines.

Earn-out only triggers above a "hurdle" (typically slightly above current performance), then shares the upside above the hurdle with the seller at a defined ratio.

Pro: clearly tied to growth, not just maintenance.
Con: structurally aligned with growth which requires the buyer to play their part.

The metric — the most consequential single decision

The earn-out metric drives everything. Common options:

Revenue

Simple to measure, hardest for the buyer to game.

Seller-friendly: revenue moves up easily, easier to hit.
Buyer-unfriendly: a seller can chase low-margin revenue to hit the target.
Conclusion: revenue earn-outs typically have a quality-of-revenue qualifier (e.g. minimum gross margin %).

Gross profit

Revenue minus direct costs. Better aligned with business quality than pure revenue.

Seller-friendly: still relatively easy to measure.
Buyer-friendly: filters out unprofitable revenue.
Conclusion: a common middle ground.

EBITDA

Earnings Before Interest, Tax, Depreciation, Amortisation. The most common earn-out metric for UK M&A.

Buyer-friendly: closer to economic value.
Seller-unfriendly: many things can affect EBITDA that aren''t about business performance (e.g. one-off costs, changes to allocations, accounting policy changes).
Conclusion: needs careful definition of what''s included and excluded.

Net Profit / PBT

Worst from the seller''s perspective. Includes financing costs which the buyer controls. Avoid.

The terms that get heavily negotiated

Definition of the metric

The metric on paper is one thing. How it''s actually calculated matters more. Negotiate:

What''s included in revenue (cash-basis vs accrual; gross vs net of returns).
What''s included in costs (direct allocations vs shared services; one-offs vs ongoing).
Accounting policies (changes that affect the calculation require seller consent).
Pre-existing one-offs (legal fees from the sale itself, deal-related expenses) excluded.

Buyer control during the earn-out period

The buyer typically wants flexibility to run the business as they see fit. The seller wants protection against decisions that hurt the metric.

Standard protections to negotiate:

Buyer can''t move customers or revenue to other group entities without earn-out adjustment.
Buyer can''t close lines of business without compensation.
Buyer can''t allocate group costs to the business above a defined level.
Buyer can''t change the pricing strategy or salary structure without consent.
Buyer can''t terminate the seller''s employment "for convenience" — only for serious cause.

The seller''s rights

Access to information — monthly management accounts during the earn-out period.
Audit rights — independent verification at year-end.
Dispute resolution — typically expert determination by an agreed accountant, not litigation.

What happens on early sale of the business

If the buyer sells the business mid-earn-out, what happens? Typical resolutions:

Earn-out accelerates and is paid in full (seller-friendly).
Earn-out is calculated on performance to date (neutral).
Earn-out is forfeited (seller-unfriendly — push back hard).

What happens if the seller dies or becomes ill

Standard: earn-out continues based on business performance regardless.
Some agreements treat death as a "good leaver" event and accelerate.

The realistic outcomes

Industry data on UK SME earn-outs:

Roughly 60% of earn-outs pay out in full or close to it — businesses that performed as planned.
Roughly 20% pay partially — businesses that hit some targets, missed others.
Roughly 20% pay little or nothing — either business performance collapsed, or there was a dispute.

Sellers should plan financially as if the earn-out will be 50-60% of headline value, not 100%. Hope for the rest as upside.

Common earn-out mistakes by sellers

Trusting that "we''ll work it out fairly" — without specific contractual protections, the buyer''s definition wins.
Accepting EBITDA without defining allocations — group cost allocations can destroy the metric.
Allowing buyer "operating control" without seller protections — buyer can make changes that hurt the metric.
Accepting all-or-nothing year-end targets — one missed year kills the whole tranche.
No acceleration on early sale — buyer flips the business mid-earn-out and the seller gets nothing.
No documented dispute resolution — turns disagreements into litigation.

What to do if you''re negotiating one

Engage an M&A solicitor specifically experienced in earn-outs. Generalist commercial solicitors often miss the structural traps.
Run the projected earn-out through 3 scenarios — base case, downside, upside — and check the cash flow to you in each.
Negotiate the definitions and protections, not just the headline numbers.
Set a realistic mental anchor — assume the earn-out pays 50-60% of headline, plan around that, and the rest is upside.

Earn-out structures explained: how to negotiate one without regret