A SAFE (Simple Agreement for Future Equity) is a right to future shares, no interest, no maturity date, that converts to equity at your next priced round. A convertible note is debt: it charges interest (~4–8%), matures in 18–24 months, and converts to equity at conversion. Both let you raise now and set the valuation later via a cap and/or discount. For most pre-seed and seed rounds in 2026, the post-money SAFE is the default; convertible notes fit bridges and extensions where creditor status and a deadline matter.
Both instruments solve the same problem, raising early money without negotiating a valuation yet, so the choice comes down to a few practical differences. This is a deep dive on the instrument choice; for the whole raise, see the SaaS fundraising guide.
How each one works
| SAFE | Convertible note | |
|---|---|---|
| What it is | A right to future equity | Debt that converts to equity |
| Interest | None | ~4–8% per year |
| Maturity date | None | Typically 18–24 months |
| Sets a valuation now? | No, cap and/or discount | No, cap and/or discount |
| Creditor status | No (it's not debt) | Yes, sits ahead of equity if things go wrong |
| Complexity & cost | Low, standard YC template | Higher, it's a debt instrument |
| Best for | Pre-seed / seed speed | Bridges, extensions |
The two levers both share: cap and discount
Neither instrument prices your round today. Instead they reward early investors for their risk with one or both of:
- Valuation cap, the maximum valuation at which their money converts. A lower cap means more shares for the investor when the priced round is above it.
- Discount, a percentage (usually 15–25%) off the next round's price. The investor converts at the better of the cap or the discount.
Some also carry an MFN ("most favored nation") clause, letting an early investor adopt better terms you grant a later one. The cap is usually the term that matters most to your eventual dilution.
Post-money vs. pre-money SAFEs (this matters)
The 2026 standard is the post-money SAFE, and the difference from the old pre-money version is not cosmetic. With a post-money SAFE, the cap is measured including all the SAFE money, so the investor's ownership percentage is fixed and transparent the moment they sign, you know exactly what you sold. The trade-off: dilution from later SAFEs falls on you, not on earlier SAFE holders. It's clearer, which is why it won, but it means you must track cumulative dilution as you stack rounds.
The stacking trap
The most common way founders get surprised: raising a series of SAFEs at different caps over time, "just another $250K on a SAFE", without tracking what they all convert into together. A pile of uncapped or high-cap SAFEs can convert into far more ownership than you expected when the priced round finally lands. Before you sign the next one, model the cumulative conversion in the dilution calculator or the cap table calculator.
When to use which
- Use a SAFE for a standard pre-seed or seed raise (~$500K–2M) from angels and small funds. It's fast, cheap, universally understood, and needs no board or maturity machinery.
- Use a convertible note for a bridge or extension, when a maturity date and creditor status give the investor comfort, or when you specifically want a deadline that forces the next event. Notes also suit situations where the investor wants the downside protection of being a creditor.
- Move to a priced round at Series A, once there's a lead investor to set the valuation and the full term sheet. See the term sheet explained.
Frequently asked questions
What is the difference between a SAFE and a convertible note?
A SAFE is a right to future equity with no interest and no maturity date. A convertible note is debt: it charges ~4–8% interest, matures in 18–24 months, and gives the investor creditor status. Both defer valuation to the next priced round via a cap and/or discount.
Is a SAFE better than a convertible note?
For most pre-seed and seed raises, yes, it's simpler, cheaper, and has no debt maturity hanging over you. Notes are better for bridges and extensions where a deadline or creditor protection matters. Neither is universally "better"; it depends on the situation.
What is a valuation cap on a SAFE?
The maximum valuation at which the SAFE converts to equity. If your priced round values the company above the cap, early investors still convert at the cap, getting more shares as a reward for early risk. It's usually the term that most affects your dilution.
What is the difference between a pre-money and post-money SAFE?
A post-money SAFE measures the cap including all SAFE money, so the investor's ownership is fixed and clear at signing, but later SAFEs dilute you, not them. The pre-money SAFE (now largely retired) measured the cap before other SAFEs, making final ownership harder to predict.
Do SAFEs and notes dilute founders?
Yes, both convert into equity at the next priced round, and that conversion dilutes founders. The amount depends on the caps, discounts, and how much you've raised. Stacking several without tracking cumulative dilution is the classic mistake.
See the dilution before you sign
Whichever instrument you choose, the number that matters is what it converts into. The dilution calculator shows your ownership across rounds, and Adlega ties the raise to your live model, dilution, runway, and the milestone the money has to buy, all in one place, with the AI CFO explaining the math. Try Adlega free while it is in beta.
Related: the SaaS fundraising guide, startup term sheet explained, SaaS valuation, and equity basics.