SAFE vs ASA vs Convertible Loan Notes: How Startup Funding Changes a UK Company

Common Startup Financing Methods in the UK

A funding instrument can affect ownership, future dilution, accounting, Corporation Tax, SEIS/EIS, shareholder rights, Companies House filings, approvals and future fundraising. These events do not always occur at the same time.

SAFE Explained

SAFE means Simple Agreement for Future Equity. Developed by Y Combinator in the United States, it lets an investor provide capital now for rights connected to equity that may be issued later.

• valuation cap
• discount
• conversion after future financing
• liquidity-event provisions
• typically no conventional interest or maturity date

A SAFE holder does not automatically become a shareholder when the SAFE is signed. UK founders should not import a US template without reviewing UK company law, accounting and tax consequences.

ASA Explained

An Advance Subscription Agreement allows an investor to pay now for shares issued later. HMRC describes ASAs as useful where funds must be raised quickly and share value cannot easily be determined.

Investor pays cash → company receives advance subscription → shares issued later.

Where SEIS or EIS is intended, HMRC expects a genuine subscription rather than a disguised loan. It should not permit refund, variation, cancellation or assignment; should bear no interest; and should have a longstop date. HMRC generally expects that date within six months.

Convertible Loan Notes Explained

A Convertible Loan Note begins as a loan. The company receives cash and owes money under the instrument, which may later convert into shares after specified events.

• principal and interest
• maturity date
• conversion trigger
• valuation cap or discount
• repayment terms
• investor protections

An SEIS/EIS-oriented ASA should not effectively be a loan; a CLN is a loan before conversion. This distinction matters where investors expect tax relief.

SAFE vs ASA vs Convertible Loan Note

The exact agreement always matters more than its label.

When Does the Investor Become a Shareholder?

Receiving £250,000 does not automatically mean the investor owns shares. A company maintains a register of members recording members and holdings. Until shares are issued and membership records change, a SAFE, ASA or CLN investor may hold contractual rights rather than shares.

Issued cap table

Who owns shares today?

Fully diluted model

Who could own shares after SAFEs, ASAs, CLNs, options and other rights convert or are exercised? Both views are useful, but they are not the same.

A Typical Funding Timeline

What UK Corporate Approvals Should Founders Consider?

Issuing shares is not simply a bookkeeping entry. Founders and legal advisers should confirm whether directors have authority to allot shares or grant rights to subscribe for or convert securities.

Section 550 may empower directors of a private company with one share class unless the articles restrict it. Other cases may require authority under section 551.

What About Pre-emption Rights?

Existing shareholders may have priority when certain new equity securities are issued. The Companies Act provides rules, exceptions and disapplication mechanisms; the articles and shareholder agreement can add requirements.

What Happens at Companies House?

When a UK limited company allots shares, it generally submits a Return of Allotment of Shares — form SH01 within one month. The statement of capital records share numbers, nominal value, classes, rights and paid or unpaid amounts.

Does signing an instrument automatically require SH01?

No. SH01 reports an allotment. If no shares were allotted, cash receipt alone may not create an SH01 filing. Corporate-law analysis still matters when rights to subscribe or convert are granted.

Documents Founders May Encounter

How Does the Accounting Differ?

None of these methods creates customer revenue merely because cash arrives. Balance-sheet treatment differs.

Under UK GAAP, classification follows contractual substance. FRS 102 says cash received before equity instruments are issued, where repayment cannot be required, creates a corresponding increase in equity to the extent of the consideration received. Convertible debt can require different analysis.

Example: £500,000 Pre-Seed Round

SAFE

Cash increases, revenue does not, shares are not necessarily issued immediately, and UK legal and accounting analysis is required.

ASA

Cash increases, revenue does not, shares issue later, and SEIS/EIS requirements should be considered before signing.

Convertible Loan Note

Cash increases, a loan obligation is created, interest may accrue, and the loan may convert later. The same £500,000 bank receipt creates three different legal, tax and accounting positions.

SEIS/EIS: Why the Instrument Matters

SEIS and EIS relief concerns qualifying share investment, subject to detailed rules. HMRC recognises ASAs but says the subscription must not in effect be a loan. An ASA converting existing debt is not considered eligible.

If investor tax relief matters, review the structure before accepting money. HMRC also recommends advance assurance before entering into an ASA where advance assurance is sought.

When Does the Cap Table Change?

Legal ownership changes when shares are allotted and membership records update. A fully diluted fundraising model may show outstanding SAFEs, ASAs, CLNs, options and warrants. Keep potential future ownership clearly separate from shares already issued.

Common Founder Mistakes

Practical Recommendations for UK Founders

Disclaimer: This article is for informational purposes only and does not constitute legal, tax or accounting advice. Financing treatment depends on the instrument's terms and the company's circumstances. Consult qualified UK legal, tax and accounting advisers before completing a financing.