How a SAFE Turns Startup Cash Into Equity at the First Priced Round

Key takeaways

• A SAFE is not a loan: it carries no interest or maturity date and only converts to stock if the startup later raises a priced round or is sold.
• The valuation cap and discount rate set how many shares an investor gets at conversion, and Y Combinator’s 2018 post-money format fixes each investor’s percentage at signing.
• Regulators and startup lawyers warn that SAFE terms vary widely and that stacking several SAFEs before a priced round can dilute founders more than they expect.

A Simple Agreement for Future Equity, or SAFE, is the contract most U.S. startups now use to take in their first outside money. Y Combinator partner Carolynn Levy drafted the original version in late 2013 as a faster, cheaper alternative to the convertible note, and the format has since become popular in the United States, Canada and Israel because of its simplicity and low transaction costs.

For founders raising a first round, the appeal is speed: a SAFE skips the interest rate, maturity date and valuation negotiation that come with a convertible note or a priced equity round. But the document still sets the terms that decide how much of the company an investor eventually owns, and those terms are locked in before any stock changes hands.

What a SAFE Is and Why It Replaced Convertible Notes

Y Combinator describes the SAFE as a short contract that lets an investor fund a startup immediately in exchange for the right to shares later, once the company raises an equity financing round. Because it is not debt, it carries no interest rate and no maturity date, so there is no repayment obligation if the startup never raises another round.

The Securities and Exchange Commission’s Office of Investor Education and Advocacy, in a May 9, 2017 investor bulletin on SAFEs used in crowdfunding, described the instrument as a promise of a future equity stake that applies only if a particular triggering event occurs, not an ownership interest in itself.

SEC’s 2017 Warning
The SEC’s Office of Investor Education and Advocacy issued a bulletin on May 9, 2017 cautioning crowdfunding investors that SAFEs are not equity and that terms vary widely between offerings.

How the Valuation Cap Works

The valuation cap sets the maximum company valuation at which the SAFE converts into shares. If the startup later raises a priced round above the cap, the SAFE investor still converts as though the company were worth only the capped amount, giving them more shares per dollar than the new round’s investors receive.

Y Combinator’s post-money template ties this directly to ownership: the percentage of the company sold to the SAFE investor equals the investment amount divided by the valuation cap. Data on deals through 2025, compiled by Carta and summarized by industry publication SaaStr, found that 61% of SAFEs use a valuation cap with no discount attached.

How the Discount Rate Works

A discount gives the SAFE holder a lower price per share than the investors in the priced round that triggers conversion. Y Combinator says discounts are commonly set between 10% and 20%; the same Carta data reviewed by SaaStr found that when a SAFE includes a discount, it is almost always exactly 20%.

Law firm WilmerHale notes the effect is larger than the headline number suggests: a 20% discount works out to roughly 25% more shares than the priced round’s investors get for the same dollar amount. Some SAFEs still combine a cap and a discount so the investor takes whichever produces the better result. WilmerHale says that hybrid structure appears in roughly 30% of SAFEs even though Y Combinator no longer recommends it.

Post-Money Vs. Pre-Money SAFEs

Y Combinator replaced its original pre-money SAFE with a post-money version in 2018. The post-money format states the valuation cap after the SAFE investment is added in, which Y Combinator says makes an investor’s resulting ownership percentage immediately transparent and calculable at signing rather than left uncertain until conversion.

That change also shifted who absorbs dilution when a startup sells several SAFEs before its priced round. Because each post-money SAFE’s percentage is fixed at signing, stacking multiple SAFEs with different caps dilutes the founders rather than the earlier SAFE holders. WilmerHale illustrates the effect with a hypothetical four-tranche raise: SAFEs totaling $4.325 million, with caps ranging from $8 million to $32 million, add up to 25.05% of the company once all of them convert.

Until conversion, the investor holds only a contract, not stock, so they have none of the rights that come with shares.

What Happens When the SAFE Converts

Conversion is automatic rather than something an investor elects. When the startup closes a qualifying equity round, outstanding SAFEs convert into the same class of preferred stock sold in that round, priced using whichever of the cap or discount favors the investor. A SAFE can also convert or pay out on a sale of the company or an IPO if that happens before any priced round.

Until conversion, the investor holds only a contract, not stock, so they have none of the rights that come with shares, such as voting rights. Pro rata rights, which let an early SAFE investor buy enough of a later round to hold their percentage steady, are not written into the SAFE itself; cap-table platform Mantle notes they are typically detailed in a separate side letter negotiated alongside it.

What Founders Negotiate, and What Regulators Warn

Founders and investors negotiate the cap, the discount, whether a most-favored-nation clause applies, and whether pro rata rights are granted through a side letter. An MFN clause lets an early SAFE investor swap into better terms if the startup later sells a SAFE with a lower cap or higher discount to someone else, though WilmerHale describes MFN terms as rarely used in practice. WilmerHale also cautions that valuation caps should be set to reflect a company’s actual progress between tranches, not chosen simply because they produce a round number.

Regulators have flagged separate risks for retail investors buying SAFEs through crowdfunding portals. The SEC’s 2017 bulletin cautioned that SAFEs are not standardized, so investors need a detailed understanding of a given offering’s terms, and warned that there is no guarantee the triggering event needed for a SAFE to convert will ever occur. A separate wrinkle involves taxes: because the holding period for the Qualified Small Business Stock exemption begins when stock is actually issued rather than when the SAFE is signed, investors can miss the deadline for that tax benefit if conversion comes late.

Photo: Coolcaesar · CC BY 4.0 · via Wikimedia Commons