Instruments
Advance subscription agreement
Also called ASA
A UK instrument in which you pay for shares in advance and they are issued at a later round's price, structured so that the payment can never be repaid as cash — which is what preserves SEIS and EIS relief.
In plain English
The ASA exists to solve a specifically British problem. SEIS and EIS relief attach to newly issued shares, and HMRC will not grant relief where the investor's money could come back as a loan repayment. A convertible note is a loan; a SAFE contains repayment and refund concepts that can create the same difficulty. The ASA is drafted so that the money is unambiguously a subscription for shares that has been paid early, with no circumstance in which it converts back into cash.
That constraint drives the two features that distinguish an ASA from a SAFE. First, it has a longstop date — typically six months, and HMRC guidance has historically been unfriendly to longstops beyond about twelve — at which the shares must be issued whether or not a funding round has happened. Second, there is no interest and no repayment provision anywhere in the document, including on insolvency.
Mechanically it behaves like a capped SAFE. You agree a valuation cap, sometimes a discount, and when the next qualifying round closes your advance converts at the better price. If the longstop arrives first, shares are issued at the cap or at a stated fallback valuation.
The relief itself is what makes this worth the trouble. SEIS and EIS provide income tax relief on subscription, capital gains exemption on a qualifying disposal and loss relief against income if the company fails — a combination that changes the arithmetic of angel investing more than any deal term on this list.
What it means for your cheque
If you are a UK taxpayer investing in a UK company, the ASA is usually the right instrument and the alternatives are usually a mistake. Signing a convertible note where an ASA was available can cost you the entire relief, which on a £20,000 investment is a larger number than any cap negotiation you will ever win.
The discipline the ASA imposes is a genuine benefit. Because the longstop forces share issuance, you cannot end up as an angel who wired money three years ago and still holds nothing. The instrument makes drift impossible, which is more than can be said for the SAFE.
Do the arithmetic
A £15,000 ASA with SEIS relief at a £2m cap
A UK higher-rate taxpayer subscribes £15,000 under an ASA at a £2m cap. The company raises at £5m nine months later. SEIS income tax relief has historically been 50% of the amount subscribed — check the current rate and limits with HMRC before relying on it.
| Amount subscribed | £15,000 |
|---|---|
| Income tax relief at 50% | £7,500 |
| Net cash cost of the investment | £7,500 |
| Shares issued at the £2m cap | 0.75% of the company |
| Value of that stake at the £5m round | about £37,500 |
| If the company fails entirely | loss relief on the £7,500 net cost, not the £15,000 |
The relief halves your downside before the deal terms do any work at all. This is why a UK angel who ignores instrument choice is leaving more on the table than one who negotiates a poor cap.
At the table
What to negotiate
- Confirm the company has, or will seek, advance assurance from HMRC. Without it you are relying on a founder's assessment of their own eligibility.
- Check the longstop date. Six to twelve months is conventional; a longer one raises questions about whether the relief survives.
- Make sure the document contains no repayment, refund or redemption language at all, including in the insolvency clauses.
- Agree the fallback valuation that applies if the longstop arrives before a round does — this is the number that will actually govern if things go slowly.
- Ask whether the company has already issued shares that could disqualify it, and whether your holding would exceed the 30% connection threshold.
Around the world
How this differs by market
Not used. A US investor in a UK company can sign an ASA but gets no SEIS or EIS relief, so the instrument's main advantage does not apply.
EUA UK instrument specifically. Ireland's EIIS, France's and Italy's startup incentives all have their own qualifying-investment rules — do not assume an ASA travels.
Advance subscription agreement: common questions
Why can I not just use a SAFE and claim SEIS?
What happens if the longstop date arrives and no round has closed?
Does the relief apply from the date I pay or the date shares are issued?
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