What is a subscription (investment) agreement?
By SuLe · Updated 16 May 2026
A subscription agreement — often called an investment agreement — is the binding contract under which an investor subscribes for (buys) newly issued shares in your company at an agreed price. It sits at the heart of a priced round alongside the shareholders' agreement and new articles of association, and it carries the warranties founders are asked to stand behind.
Key facts
- A priced round's binding documents: subscription (investment) agreement + shareholders' agreement + new articles of association.
- Unlike the term sheet, the subscription agreement is fully binding once signed.
- Subscription means new shares from the company; a share purchase agreement buys existing shares from a shareholder.
- Allotments must be reported to Companies House on form SH01 within one month (Companies Act 2006).
- A convertible round skips the full suite: a short ASA or loan note defers the valuation and the heavy paperwork.
What does a subscription agreement actually do?
It binds the investor to pay an agreed amount for a stated number of newly issued shares, and binds the company to allot them. It is the document that makes a priced round real.
Everything conditional about the round lives here: the price per share, any conditions to completion — due diligence items, or HMRC advance assurance where SEIS/EIS matters — the mechanics of completion itself, and the warranties. Once signed, neither side can simply change its mind; the term sheet's "subject to contract" protection is gone.
The label varies: some deals bundle the subscription and the ongoing governance terms into a single "investment agreement". The content matters more than the name.
How does it differ from a shareholders' agreement — and a share purchase agreement?
The subscription agreement handles the one-off act of investing. The shareholders' agreement governs the relationship afterwards, and a share purchase agreement (SPA) is a different transaction altogether — buying existing shares from a shareholder.
In a subscription, the investor's money goes into the company in exchange for new shares: it funds the business. In a share purchase, the money goes to the selling shareholder and the company receives nothing — which is why funding rounds are structured as subscriptions.
The shareholders' agreement carries the ongoing machinery: consent rights, information rights, transfer controls, leaver provisions. In a priced round the three binding documents — subscription agreement, shareholders' agreement, new articles — travel together and must be consistent with each other.
What are the warranties, and how does the disclosure letter protect you?
Warranties are statements of fact about the company — shares, accounts, contracts, IP, disputes — made to the investor in the subscription agreement. If one is untrue and undisclosed, the investor may claim for the resulting loss.
The protection mechanism is the disclosure letter: anything honestly disclosed against a warranty stops being a potential claim and becomes a known risk the investor accepted. The discipline of preparing it — checking every warranty against reality — is where founders earn their sleep.
Scope is negotiable: who gives the warranties (the company alone, or founders personally), subject to what caps, and for how long. Take advice before personally standing behind anything.
What actually happens at completion?
Money moves, shares are issued and the filings follow — in that order, on the timetable the agreement fixes.
On completion day the investors pay their subscription monies, the board resolves to allot the shares — with authority to allot and pre-emption rights dealt with under the Companies Act 2006 — and the register of members is written up. The register entry is what legally makes an investor a shareholder; certificates follow.
Companies House must then receive form SH01 within one month of the allotment. If investors are claiming SEIS or EIS, remember relief attaches to the share issue — check the conditions and any advance assurance position before completion, because the issue date is what claims hang on.
| Step | What happens | Paperwork |
|---|---|---|
| Signing | Subscription agreement, shareholders' agreement and new articles signed | The binding round documents |
| Conditions | Outstanding conditions satisfied (diligence items, SEIS/EIS advance assurance) | Condition confirmations |
| Completion | Investors pay; board approves the allotment | Board minutes and resolutions |
| Share issue | Register of members written up; certificates issued | Register of members, share certificates |
| Filing | Allotment reported to Companies House | Form SH01 — within one month of allotment |
When do you need a subscription agreement — and when is an ASA enough?
You need one for a priced round: any round that fixes a valuation and issues shares now. A convertible round runs on a short ASA or convertible loan note instead, with the valuation deferred.
The full suite — subscription agreement, shareholders' agreement, new articles — costs time and legal fees, which is exactly what convertibles let you postpone while the amounts are small. The trade-off arrives later: everything deferred lands at the priced round, alongside the convertibles converting into shares.
A well-trodden seed path: ASAs from angels first, then a priced round with a subscription agreement once a lead investor sets terms. If that is your route, keep the ASA terms clean so conversion at the round is mechanical.
Worked example
Sofia and Patrick's edtech platform closes a £750,000 seed round: £600,000 from a seed fund and £75,000 from each of two angels. The subscription agreement prices the round at £1.50 per share — 500,000 new ordinary shares against the 1,500,000 in issue, a £2.25m pre-money and £3m post-money valuation, 25% to the new investors.
The agreement carries warranties from the company; the disclosure letter flags a pending trademark objection, so the investors take that risk with open eyes. On completion day the funds land, the board approves the allotment, the register of members is written up, and the SH01 reaches Companies House twelve days later — comfortably inside the one-month window.
Where founders go wrong
Treating signature as the finish line
— the money moves at completion, and the shares only exist once the register of members is written up; chase every step.Signing warranties without a proper disclosure exercise
— the disclosure letter is your protection; an hour spent disclosing beats a warranty claim later.Confusing subscription with purchase
— investors expect their money in the company (new shares), not in a founder's pocket (existing shares); any founder sell-down needs separate, explicit negotiation.Missing the SH01
— allotments must reach Companies House within one month; it is basic hygiene the next round's due diligence will check.
Related questions
Is a subscription agreement legally binding?
Yes — completely, unlike the term sheet that preceded it. Once signed, the investor is bound to subscribe and the company to allot, subject to any conditions in the agreement. That is why the negotiation happens at term sheet stage and the drafting battle happens here. [More: What is a term sheet — and is it legally binding?]
What are warranties in an investment agreement?
Statements of fact about the company — its shares, accounts, contracts, IP and disputes — confirmed to the investor at signing. If one turns out to be untrue and undisclosed, the investor may claim for the loss. The disclosure letter is how you qualify them honestly. [More: What are warranties in an investment agreement?]
Subscription agreement vs share purchase agreement — what's the difference?
A subscription agreement issues new shares: the investor's money goes into the company. A share purchase agreement (SPA) transfers existing shares: the money goes to the selling shareholder. A funding round is a subscription — investors want their cash funding the business, not buying out early holders. [More: What is a share purchase agreement (SPA)?]
What other documents does a priced round need?
A shareholders' agreement governing the ongoing relationship, and new articles of association carrying the share rights. The subscription agreement handles the one-off act of investing. In a convertible round you skip all three for now — a short ASA or loan note defers the valuation and the paperwork. [More: What documents do I need to close a seed round in the UK?]
When must the SH01 be filed?
Within one month of the allotment, at Companies House. It reports the new shares — how many, at what price — and next-round due diligence will check it was done. The company also updates its register of members, which is what legally makes the investor a shareholder. [More: What is an SH01 and when must I file it?]
The subscription agreement is where the deal stops being a conversation: warranties, conditions and completion mechanics all bind on signature. A SuLe solicitor can review the drafting — and run the disclosure exercise properly — before you commit. Book a free term sheet review and go into completion with clean paperwork.
Keep reading: What is a term sheet — and is it legally binding? · What should a UK seed-stage term sheet include? · What is a priced round vs a convertible round? · What is an advance subscription agreement (ASA)? · What documents do I need to close a seed round in the UK? · What are warranties in an investment agreement?
Primary sources: Companies Act 2006 · HMRC — advance assurance for venture capital schemes
