You wire money into a company months before anyone agrees what it's worth. The valuation gets set at the next proper round - the priced one, with lawyers and a new share class - and your early cheque only turns into shares then. So the obvious question: at what price? Convert at the same number the later investors pay and you've taken all the early risk for none of the reward. The valuation cap and the discount are the two levers that fix that, and they reward a careful read before you sign anything that defers a price.
Both ride on the same family of instruments - a SAFE, a convertible loan note, or in the UK an advanced subscription agreement (ASA). All three take your money now and issue the shares later. The cap and the discount are simply the two ways the paperwork decides how cheaply your money converts when that moment comes.
The cap is a fixed ceiling you negotiate today. The discount floats with whatever the next round turns out to be.
What is a valuation cap?
A valuation cap is a ceiling on the company valuation used to convert your money into shares. You negotiate the number up front. When the priced round eventually lands, you compare its valuation to your cap: if the round is priced above the cap, you convert as though the company were worth the lower capped figure, not the higher round figure. That lower implied price means your money buys more shares per pound than the new investors' money does.
Say you put £50,000 in on a £4m cap. The company does well and raises its next round at an £8m pre-money valuation. The new investors are paying at £8m; you convert at £4m. Your money buys shares as though the company were half the price the round implies - roughly twice the shares your £50,000 would have bought at the round price. That gap is the cap doing its job: paying you for having gone in when the outcome was far less certain.
The flip side matters too. If the next round is priced at or below your cap, the cap simply doesn't bite - there's no ceiling to apply, because the round itself is already at or under it. A cap is protection against the company doing well and pricing you out of the upside; it does nothing if the company raises flat or down. That's why the cap number is the single most negotiated term on these instruments: it's a live bet on how far the company climbs before the next price is struck.
What is a discount?
A discount is simpler. It converts your money at a set percentage below the per-share price the new investors pay - typically somewhere between 10% and 30%. On a 20% discount, if the priced round sets shares at £1.00 each, your money converts as though they cost 80p. Same cheque, more shares.
The defining feature is that a discount has no fixed reference number of its own. It floats. Whatever the next round is priced at, the discount takes its set percentage off that. So a discount rewards you relative to the new money no matter where the round lands - but it can't, on its own, protect you from a round priced far higher than you expected. A 20% discount off a price that has quadrupled is still a price four-fifths of the way up. That's the structural reason caps exist alongside discounts rather than instead of them.
What happens when a deal has both?
Most SAFEs and convertibles carry both a cap and a discount, and the near-universal convention is that they don't stack. You don't get the discount applied on top of the capped price. Instead the instrument applies whichever of the two gives you the lower conversion price - the better of the two, from the investor's side.
The arithmetic is worth seeing once. Take the £4m cap and a 20% discount on the same instrument, and a priced round at an £8m pre-money valuation. The cap holds your conversion to £4m; the discount would give you 80% of the £8m round, an effective £6.4m. The cap is the lower of the two, so the cap wins and you convert at £4m. Now flip it - suppose the round comes in at just £4.5m. The cap would still hold you to £4m; the discount would give you 80% of £4.5m, or £3.6m. This time the discount is the better deal, and that's what applies. The two levers swap which one bites depending on how high the round prices.
One drafting point that catches people out: the agreement should say in plain terms that you get the better of cap and discount, not both. A poorly drafted instrument that's silent or ambiguous on this is exactly the kind of thing worth flagging to a lawyer before you sign. The difference between "better of" and "both" can be a material number of shares.
Why early money gets a cap or a discount
Strip away the mechanics and the logic is straightforward. The investor going in before a valuation is set is backing the company with less information, less traction and less proof than the people who write cheques in the priced round. The cap and the discount are the compensation for that. They make sure the early money ends up paying less per share than the later, better-informed money - which is the whole point of being early.
An uncapped, undiscounted instrument hands the early investor no such reward: they'd convert at the full round price, having taken the early risk for nothing extra. You do see uncapped SAFEs, usually when a company holds all the cards, but for most UK angel deals a cap, a discount, or both is the norm. None of this is peculiar to one instrument - the same machinery sits on a SAFE, a convertible note and an ASA alike.
The UK wrinkle worth knowing
Caps and discounts are price mechanics; they don't, by themselves, decide whether a deal qualifies for the UK tax reliefs. But the instrument they sit on can. A standard convertible loan note is a loan, and a US-style SAFE is often drafted for Delaware rather than Companies House - and SEIS and EIS relief require a genuine subscription for newly issued shares with no right to your money back. The common UK fix is the ASA, structured as an irreversible payment for shares to be issued later, with no repayment and no interest, which can carry a cap and a discount just as a SAFE does.
The reliefs are generous enough to be worth protecting: under SEIS, 50% income tax relief on up to £200,000 a year; under EIS, 30% on up to £1,000,000 (or £2,000,000 where at least £1,000,000 goes to knowledge-intensive companies), each with a three-year minimum hold. Both need HMRC advance assurance before the money goes in, and a certificate (SEIS3 or EIS3) to claim. The detail for investors is set out in HMRC's guidance: gov.uk venture capital schemes (tax relief for investors), with the company-side EIS conditions and the April 2026 changes on the EIS application guidance.
So what actually matters here?
The cap number, mostly - it's the term that moves your eventual share count the most, and the one founders and investors fight over hardest. After that, the discount, the events that trigger conversion, and, in the UK, whether the instrument keeps SEIS or EIS alive. A low cap is generally friendlier to the early investor and tougher on the founder's dilution, but a generous cap on a company that goes nowhere is worth nothing, and the cap is only one line in a longer document.
A line we'll keep stating plainly, because it's how we cover this. Nothing here tells you whether to do a given deal or what cap to accept - that isn't our job, and it isn't advice. These mechanics move price and risk around; they don't remove the risk, and early-stage companies remain among the most likely places to lose the entire stake. The tax treatment depends on your circumstances and on rules that shift with each Budget. This piece is general information, not financial or investment advice - take FCA-regulated advice before you commit capital.
Frequently asked questions
What is a valuation cap?
A valuation cap is a ceiling on the company valuation used to convert early money - on a SAFE, convertible note or advanced subscription agreement - into shares at the next priced round. If the priced round values the company above the cap, the early investor still converts as though the company were worth the lower capped figure, so the money buys more shares per pound than the new investors get. If the round comes in at or below the cap, the cap simply does not bite. It rewards the investor who went in before a price was set.
What is a discount on a SAFE or convertible?
A discount converts the early money at a set percentage below the per-share price the new investors pay in the priced round, commonly 10% to 30%. On a 20% discount, your money converts as though the shares cost 20% less than the headline round price, so the same cheque buys more shares. Unlike a cap, a discount has no fixed reference number - it floats with whatever the next round is priced at.
What happens when a deal has both a cap and a discount?
Most instruments that carry both apply whichever produces the lower conversion price for the investor - not both stacked together. You work out the price the cap implies and the price the discount implies, and the investor converts at the cheaper of the two. In a round priced well above the cap, the cap usually wins; in a round priced close to the cap, the discount can give the better number. The drafting should say explicitly that it is the better of the two, not the sum.
Why do early investors get a cap or a discount at all?
Because they take more risk than the investors who follow. Putting money in before a valuation is agreed means backing the company with less information and less proof. The cap and the discount are the compensation for going first: they ensure the early cheque ends up paying less per share than the later, better-informed money. Without them, an early investor on an uncapped, undiscounted instrument would convert at the full round price and get no reward for being early.
Does a low valuation cap mean a better deal?
A lower cap means a lower conversion price and so more shares per pound, all else equal, which is generally favourable to the early investor and tougher on the founder's dilution. But the cap is only one term among many, and a generous cap on a weak company is worth less than a modest cap on a strong one. The number that matters is what the money ultimately buys and whether the company gets anywhere. This is general information, not financial advice; take FCA-regulated advice before investing.