What Is a SAFE?
A SAFE, or Simple Agreement for Future Equity, lets an investor give a startup money now in exchange for shares later, usually at the next priced round.
How it works
A SAFE is a contract, not a loan and not yet stock. The investor pays the company; the contract promises shares when a triggering event happens, usually a priced equity round. Because there is no debt, there is no interest and no repayment date. SAFEs were created by Y Combinator and are widely used for early rounds because they are short and cheap to complete.
The main terms are a valuation cap, which sets the highest valuation at which the SAFE converts, and sometimes a discount, which gives the investor a lower price than new investors pay. Versions differ, including post-money SAFEs, where the cap includes all SAFE money. Read the exact form used.
SAFE vs convertible note
A convertible note is debt: it usually accrues interest and has a maturity date when repayment or conversion can be demanded. A SAFE has neither. That makes a SAFE simpler and gentler on the founder, while a note gives the investor stronger claims. Both convert into shares at a later round.
Example
An investor puts $100,000 into a SAFE with a $5 million post-money cap. At the next round, the company is valued at $10 million. Because of the cap, the SAFE converts as if the valuation were $5 million, giving the investor 2 percent ($100,000 divided by $5 million) of the pre-round company, before the new round's dilution. Without the cap, the same money would buy less.
Common mistakes
- Not modeling how several SAFEs with different caps stack up on the cap table.
- Treating a SAFE as free money with no ownership cost.
- Using the wrong SAFE version without understanding the differences.
- Skipping legal review because the form is standard.
Frequently asked questions
What is a SAFE in startup funding?
A SAFE is an agreement where an investor funds a startup now and receives shares later, typically at the next priced round. It is not debt, so it has no interest or maturity date.
What is the difference between a SAFE and a convertible note?
A convertible note is a loan that accrues interest and has a maturity date, while a SAFE is not debt and has neither. Both convert to equity later, usually with a valuation cap or discount.
Related terms
Go deeper
- SAFE vs Convertible Note: Which Is Better for Founders? GuideSAFE vs convertible note explained: how each works, valuation caps, discounts, interest and maturity, with a worked example and the trade-offs for founders.
- Startup Funding Stages: Pre-Seed to Series C Explained GuideStartup funding stages explained in plain English: pre-seed, seed and Series A, B and C, what each round is for, what investors expect and how rounds are sized.
All 70 startup terms · More terms starting with S · Guides
General information, not legal, tax or financial advice. Reviewed 11 November 2026.