Understanding SAFEs & Convertible Notes: A Founder’s Guide
SAFEs (Simple Agreements for Future Equity) and convertible promissory notes are the two most common instruments used to raise pre-seed and seed capital. Both allow companies to raise money without setting a valuation — deferring the pricing decision to a later priced equity round. While they serve similar purposes, they have meaningful structural differences that affect founder economics, investor protections, and the complexity of your cap table. This guide explains how each instrument works and what founders should consider when negotiating terms.
What Is a SAFE?
A SAFE is an agreement in which an investor provides capital to a company in exchange for the right to receive equity in a future priced financing round. SAFEs were developed by Y Combinator in 2013 as a simpler alternative to convertible notes. Unlike notes, SAFEs are not debt — they do not accrue interest, have no maturity date, and do not need to be repaid. SAFEs convert into equity when a triggering event occurs, typically a priced equity financing (Series A or equivalent).
Key SAFE Terms
Valuation Cap: The maximum valuation at which the SAFE converts into equity. If the priced round values the company above the cap, the SAFE investor converts at the cap — effectively receiving a lower price per share and more equity. The cap is the most important economic term in a SAFE and is the primary point of negotiation.
Discount Rate: An alternative (or additional) conversion benefit that gives the SAFE investor a percentage discount to the price per share paid by the new investors in the priced round. A typical discount is 15-25%. If a SAFE has both a cap and a discount, the investor converts at whichever method produces the lower price per share (i.e., more equity).
MFN (Most Favored Nation) Provision: Gives the SAFE investor the right to adopt the terms of any subsequent SAFE issued by the company on more favorable terms. MFN provisions are most common in uncapped or cap-only SAFEs and protect early SAFE investors from being disadvantaged by later investors who negotiate better terms.
Pro Rata Rights: The right to participate in the priced financing round that triggers conversion, allowing the SAFE investor to maintain their ownership percentage. Pro rata rights are increasingly standard in SAFEs from institutional seed investors.
What Is a Convertible Note?
A convertible note is a loan that converts into equity upon a triggering event — typically a qualified financing. Unlike SAFEs, convertible notes are debt instruments: they have a principal amount, accrue interest, and have a maturity date by which they must be either repaid or converted. Convertible notes predate SAFEs and remain common, particularly in markets and with investors who prefer the additional protections that debt instruments provide.
Key Convertible Note Terms
Interest Rate: Convertible notes accrue interest, typically at 4-8% per annum. When the note converts, the accrued interest converts into equity along with the principal — meaning the investor receives slightly more equity than they would under a SAFE with the same cap. While the interest rate is usually not heavily negotiated, the economic impact compounds over time.
Maturity Date: The date by which the note must be repaid if it has not converted. Typical maturities range from 18-24 months. If the company has not raised a priced round by maturity, the note creates a legal obligation to repay — which most early-stage companies cannot do. In practice, maturity dates are usually extended by agreement, but they give the noteholder leverage in the negotiation.
Valuation Cap & Discount: Convertible notes use the same cap and discount mechanics as SAFEs. The economic conversion analysis is identical — the investor converts at whichever method produces the lower price per share.
Qualified Financing Threshold: The minimum amount of capital that must be raised in the priced round for the note to automatically convert. Typical thresholds range from $500K to $2M. If the priced round falls below the threshold, conversion may be optional for the noteholder, giving them the choice between conversion and repayment.
SAFE vs. Convertible Note: Key Differences
Debt vs. Equity: Convertible notes are debt and appear on the balance sheet as a liability. SAFEs are not debt — they are equity instruments that do not create repayment obligations. This distinction matters for accounting, financial reporting, and the company’s negotiating position at maturity.
Interest Accrual: Notes accrue interest; SAFEs do not. Over an 18-24 month period, interest accrual modestly increases the investor’s equity upon conversion. The difference is typically small but compounds with larger note amounts.
Maturity Pressure: Notes have a maturity date that creates a legal obligation to repay. SAFEs have no maturity — they remain outstanding until a triggering event occurs. This distinction gives noteholders leverage that SAFE holders do not have, which can affect the company’s negotiating position if the fundraising timeline extends.
Complexity: SAFEs are simpler documents — typically 5-7 pages with fewer negotiated terms. Convertible notes are more complex, involving promissory note mechanics, subordination provisions, and default terms. The simplicity of SAFEs reduces legal costs and speeds up the fundraising process.
Negotiation Considerations for Founders
Cap vs. No Cap: Uncapped SAFEs and notes give investors no ceiling on the conversion price, meaning they convert at whatever valuation the Series A sets. While this is better for founders in theory, it can make subsequent fundraising harder — sophisticated investors may decline to invest if early investors have uncapped instruments that create misaligned incentives.
Stacking Multiple SAFEs: If you raise seed capital from multiple investors using SAFEs at different caps, the cap table complexity increases. Each SAFE converts independently, and the dilution from multiple SAFEs stacking on top of the Series A round can be surprising. Model the fully diluted cap table — including all outstanding SAFEs — before committing to terms.
Side Letters: Institutional seed investors may request side letters with additional provisions — such as information rights, board observer seats, or participation rights. Evaluate these requests carefully, as they add governance complexity and may set precedents for later investors.
This guide provides general legal information and does not constitute legal advice. The right fundraising instrument depends on your specific circumstances, investor preferences, and strategic objectives. Contact Montague Law to discuss your fundraising strategy.