Convertible notes are debt instruments with maturity dates and accruing interest, creating real legal obligations that can trigger insolvency if the company fails to raise its next round before the maturity date. SAFEs carry none of these risks — they have no maturity date, no interest, and no repayment obligation. A startup that misses its fundraising timeline with outstanding convertible notes faces potential default; one with outstanding SAFEs simply continues operating.
The debt nature of a convertible note creates obligations that SAFEs simply don't carry. Interest accrues — typically 5–8% annually — increasing the effective conversion amount at every subsequent round. A maturity date, usually 18–24 months out, means the company technically owes principal plus interest if a financing hasn't closed. "Most of the time the note rolls or converts and nobody sweats the maturity date," Gurpreet Bal says. "But I've seen situations where a founder is staring down a maturity date with no deal in sight and a noteholder who has suddenly found religion about their creditor rights. It's a bad spot." SAFEs eliminate that scenario entirely.
Investors push for convertible notes because debt treatment provides certain advantages: notes have legal priority over equity in a liquidation, interest accrual increases the investor's conversion amount, and the maturity date creates a forcing mechanism that pressures the company to raise its next round or negotiate terms. For investors who are uncertain about the company's prospects, debt treatment provides a modest floor that SAFE instruments do not.
"SAFEs are for investors who are either lazy or so desperate to get into a hot deal that they'll take whatever the company is offering," Gurpreet Bal says, without much hesitation. He is not being entirely ungenerous — the SAFE's simplicity is by design, and many sophisticated seed investors prefer it for exactly that reason. But the note persists because it gives investors creditor status, which matters for portfolio accounting in certain fund structures, and because the maturity date functions as a forcing mechanism on companies that might otherwise delay a priced round indefinitely. "If you have a strong business and good leverage, push for a SAFE," he says. "If the investor needs a note for their LPs, make sure the maturity is long enough to be meaningless."
Interest accrual on a convertible note converts into additional shares at the conversion event, meaning the note holder receives more equity than a SAFE investor who put in the same principal at the same cap. On a $500K note at 8% annual interest, a two-year runway to conversion creates $80K of accrued interest that converts alongside principal — giving the investor approximately 16% more shares than the same $500K on a SAFE. The effect compounds over time.
The math is not dramatic at the individual note level but compounds across a typical seed round. A $500,000 note at 6% annual interest held for 20 months converts as roughly $550,000 in equity at Series A. Multiply that across several seed notes from different closing dates and interest rates, and the accrued interest can represent meaningful additional dilution that founders didn't fully model when they signed. Gurpreet Bal routinely walks founders through the cap table impact of interest accrual before they choose between instruments — "it's not a reason to panic, but it's a reason to know what you're signing."
Convertible notes may be appropriate in jurisdictions where SAFEs are not well recognized, in bridge financing situations where the investor requires debt treatment for fund accounting purposes, or when the founder needs the maturity date as a forcing mechanism to create urgency around the next round. In international fundraising contexts, notes also provide clearer classification under local securities and tax law in jurisdictions that have not adopted SAFE equivalents.
Convertible notes remain the better instrument in a few specific situations. Bridge financings between priced rounds often use notes because the parties have an existing priced structure to reference. Institutional investors who require debt instruments for their own fund accounting sometimes cannot use SAFEs. In geographies outside of Silicon Valley, notes remain more common simply because local counsel and investors are more familiar with them. "Outside the Bay Area, you'll still see notes more often than SAFEs in a lot of markets," Gurpreet Bal notes. "That's changing, but it hasn't fully changed."
Founders consistently miss that a post-money SAFE locks in the investor's ownership percentage at signing, meaning the option pool expansion at Series A — which typically dilutes everyone else — falls entirely on the founders and employees. A pre-money SAFE does not lock in the percentage, so everyone including the SAFE investor is diluted by the option pool. At the same cap level, a post-money SAFE is materially more expensive for founders than a pre-money SAFE.
Even when founders correctly choose a SAFE over a note, they often miss the more consequential decision: pre-money versus post-money. Post-money SAFEs — the current Y Combinator standard — calculate conversion ownership on a post-financing basis, which can produce a surprising "SAFE conversion tax" at Series A that dilutes founders more than a pre-money SAFE would have. Gurpreet Bal recommends sticking with pre-money SAFEs whenever possible to avoid that dynamic. "The Y Combinator math sounds clean until you see what it does to your cap table at the A," he says. "It's not always the better deal for founders even though it comes in a standard form."
Gurpreet S. Bal is a corporate partner with 16 years advising on private equity, merger transactions, and public offerings for companies and investors at three of the world's top law firms. He has represented clients in hundreds of transactions with aggregate deal value exceeding $60 billion across AI, semiconductors, fintech, and emerging technology. For more information and to get in touch, visit gurpreetbal.com.