Should I Use a SAFE or a Convertible Note for My First Raise?
Your first check is coming in. The investor says they are flexible on structure.
Now you have to decide: SAFE or convertible note. Most first-time founders either pick the one they have heard of before or defer to whatever the investor prefers. Both choices can cost you money and control if you do not understand what you are choosing.
What Each Structure Actually Does
A SAFE Is Not a Loan
A Simple Agreement for Future Equity (SAFE) converts to equity at a future priced round. There is no interest rate, no maturity date, and no obligation to repay. It is one of the most common structures for pre-seed and seed rounds, widely used in pre-priced financings.
The dominant form is the post-money SAFE, introduced by Y Combinator. Post-money means the valuation cap is calculated after the SAFE money is included in the cap table, making dilution more predictable for both sides.
A Convertible Note Is a Loan That Converts
A convertible note is debt. It accrues interest, has a maturity date, and converts to equity at a priced round — or must be repaid if no round closes. The maturity date creates a risk many early-stage founders underestimate: if the company has not raised a priced round by the maturity date, the noteholder may demand repayment or negotiate conversion terms that may not be favorable to the company.
Both Instruments Include Cap and Discount Mechanics
Both SAFEs and convertible notes typically include:
- a valuation cap (the maximum price at which the instrument converts to equity)
- a discount rate (a percentage reduction on the Series A price for early investors)
- sometimes include most-favored-nation (MFN) provisions
The cap and discount protect early investors. They dilute founders at the priced round. Model both before you sign.
When Each Structure Fits
SAFEs are faster, simpler, and well-suited for most pre-seed and seed raises. Convertible notes are more appropriate when:
- the investor or jurisdiction requires debt documentation
- the founders want to negotiate specific repayment protections
- the raise involves a non-US investor with different legal expectations
3 Mistakes Founders Make Here
Mistake #1: Defaulting to What the Investor Prefers
Some investors prefer convertible notes because the debt structure gives them additional protections at maturity. Founders who defer to investor preference without understanding why often:
- accept maturity dates shorter than their expected timeline to a priced round
- fail to negotiate interest rates that are below market
- miss the opportunity to use a SAFE, which often involves fewer investor control provisions than debt instruments
The structure should match your needs, not just your investor’s preference.
Mistake #2: Not Modeling the Cap Table Before the Priced Round
A SAFE or convertible note with a low valuation cap can significantly dilute founders at the priced round. Founders who do not model the conversion often:
- discover the dilution impact only when the Series A term sheet arrives
- fail to negotiate the cap upward because they did not know it was too low
- stack multiple SAFEs with different caps, compounding the dilution at conversion
Run the cap table math before you take the first dollar—it is much harder to fix later.
Mistake #3: Assuming the Note Will Definitely Convert
First-time founders often assume the priced round is a certainty. It is not. A convertible note that hits its maturity date without a priced round creates a legal obligation:
- the noteholder may have the right to demand repayment, depending on the terms of the note
- or they can force a conversion at terms that may not be favorable
- the company may face a default scenario without sufficient cash to resolve it
Know the maturity date. Build runway past it.
Before You Sign, Work Through This
Before you commit to either structure, work through this:
☐ Have I modeled what my cap table looks like after conversion at the valuation cap?
☐ Do I understand the difference between pre-money and post-money SAFEs?
☐ If this is a convertible note, does my runway extend past the maturity date?
☐ Have I compared the valuation cap to what I expect my priced round valuation to be?
☐ Do I know whether the note accrues simple or compound interest?
☐ Has startup-specialized counsel reviewed the final instrument before I sign?
If you cannot answer yes to all of these, you are not ready to take this money yet.
Bottom Line
SAFEs and convertible notes are both common instruments. They are not interchangeable. The right choice depends on your timeline, your investor relationships, and your cap table—not on which structure you happened to hear about first. Model the conversion before you sign, not after.
Ready to Understand the Instruments Behind My First Round?
Join our First Time Founders Masterclass on May 19 to learn more and ask questions.
Reserve your seat: https://howtoraisevcround.com/how-to-raise-priced-round-2
Sources Used
- Y Combinator, The Post-Money SAFE: A Guide for Founders, https://www.ycombinator.com/library/By-the-post-money-safe
- Carta, SAFE vs. Convertible Note: What’s the Difference?, https://carta.com/learn/startups/financing/safe-vs-convertible-note/
- Cooley, Pre-Seed Financing Instruments: SAFE vs. Convertible Note, https://www.cooleygo.com/safe-vs-convertible-notes-pros-cons/
- Fenwick & West, Convertible Note Financing for Early Stage Startups, https://www.fenwick.com/insights/publications/convertible-note-financing-for-early-stage-startups