How much does a bridge SAFE dilute me?

On a worked example of a 2M SAFE at a 15M cap with a 20 percent discount converting into a 5M Series A at a 20M pre-money, the bridge alone costs founders roughly 5 to 6 percent, with total dilution around 22 percent once the Series A and an option pool refresh are included. It scales roughly linearly with bridge size if the cap holds.

Will a bridge round hurt my Series A?

Not by itself, but the structure gets read closely. Series A investors look at three things: who led it, at what price, and how long it bought. Insider-led at a flat valuation reads as conviction. Outsider-led at a steep discount suggests your insiders declined. Six months of runway is normal, three months is concerning, and twelve months can suggest you raised prematurely.

Should I use a SAFE or a convertible note for a bridge?

A post-money SAFE closes fastest, often in one to three weeks, with no interest or maturity date, which suits a short milestone gap. A convertible note carries roughly 5 to 8 percent interest and a 12 to 24 month maturity, which adds a deadline. If your existing lead has conviction and will price an extension at the prior round's terms, take that instead.

When should I cut burn instead of raising a bridge?

When you cannot name the specific milestone the money buys. A bridge that funds general runway rather than a fundable proof point postpones the same conversation at a worse valuation with more dilution. If the honest answer to what changes in six months is more time, the problem is not capital.

The Bridge SAFE: What to Do When Your Seed Round Is Not Coming

Q: What is the difference between a bridge round and an extension round?

A bridge is unpriced interim financing, usually a SAFE or convertible note, that converts at your next priced round with a cap and discount. An extension is priced at the same terms as your prior round: same valuation, same liquidation preference, same anti-dilution. The extension signals insider conviction. The bridge signals a runway operation.

A bridge SAFE is unpriced interim capital that converts at your next priced round, usually with a cap and discount. Raise one when a specific milestone is close and fundable. It costs roughly 5 to 6 points of dilution on a typical structure, and your Series A investors will read who led it, at what price, and for how long.

The word "bridge" is doing a lot of work in that sentence, and it is worth being precise about it, because founders use it to mean two different instruments with very different signals attached.

Bridge and extension are not the same thing

Spectup's breakdown of bridge rounds draws the line cleanly. A bridge is unpriced: a SAFE or convertible note that converts at your next priced round, carrying a discount and a cap. An extension is priced at the same terms as your prior round, with the same valuation, liquidation preference, and anti-dilution mechanics.

Their one-line summary is the part to remember: the extension signals insider conviction, the bridge signals a runway operation.

That difference is not cosmetic. If your existing investors are willing to put money in at the prior round's price, they are telling the market they believe the last valuation still holds. If they are only willing to go in unpriced with a discount, they are declining to restate that opinion. Both can be fine. They are not the same message, and the people reading your cap table at Series A know the difference.

The practical implication is a sequencing rule. Ask your lead about a priced extension first. The bridge is what you do when they will not price it.

The data is softer than the confidence around it

You will hear that bridges are normal now, often with a specific number attached. Treat those numbers carefully, because the good ones come with caveats their citers usually drop.

Value Add VC's piece on seed extension rounds puts roughly 38% of seed-funded startups raising one before a priced Series A, with a median of $1.5M to $3M, at flat or a 10 to 15 percent step-up, buying 9 to 15 months. Useful directional shape. But read their own note on methodology: the figures are blended estimates synthesized from Carta, PitchBook, and AngelList reporting, and they describe them as directional, not official.

That is an honest disclosure and it should change how you use the number. "38% of seed startups raise an extension" is a reasonable estimate of a trend. It is not a benchmark you can hold your round against, and anyone quoting it as hard data has not read the footnote.

What you can take from the range of available reporting is directional and still useful: bridges went from a distress signal to a common instrument, and raising one no longer marks you. What you cannot take is a precise threshold for what is normal. There is no published figure clean enough to tell you whether your bridge is early or late. Your milestone tells you that, not the market.

Pick the instrument, then the size

Instrument	Typical terms	Speed	Best when
Post-money SAFE	Cap and discount, no interest, no maturity	Fastest, often 1 to 3 weeks	A short milestone gap where speed matters most
Convertible note	Roughly 5 to 8 percent interest, 12 to 24 month maturity	Slower	Larger bridges, or investors who think in debt
Priced extension	Prior round's valuation and terms	Slowest	Your existing lead has conviction and will price it

Two notes on the note. SeedBlink's analysis of bridge rounds puts current discounts at 20 to 30 percent, interest at roughly 5 to 7 percent and typically paid in kind rather than cash, with maturities shortened to 12 to 24 months. The maturity is the part founders underweight. It is a deadline with legal consequences, and a note maturing before your Series A closes is a problem you scheduled for yourself.

SeedBlink also records a founder capping a convertible at €1M when investors offered €1.5M, on the reasoning that a €1M instrument converts to something closer to €1.3M in equity once discount and interest compound. That is the right instinct. A bridge is priced in ownership, not euros, and the conversion is always larger than the headline.

What it costs

Spectup works a clean example. Take a $2M SAFE at a $15M cap with a 20 percent discount, converting into a $5M Series A at a $20M pre-money. At conversion the holder compares two prices: the $15M cap, and the $20M pre-money less 20 percent, which is an effective $16M. The SAFE converts at the lower, so the cap governs.

The bridge alone costs founders roughly 5 to 6 percent. Add the Series A and an option pool refresh and total dilution lands near 22 percent. It scales roughly linearly with bridge size if the cap holds.

Sit with that. A $2M bridge, raised because the seed slipped by two quarters, costs about the same ownership as a decent chunk of a priced round, and buys no new investor, no board seat, no validation event. It is the most expensive kind of time you can buy.

Which is exactly why the milestone question is the whole decision. If the mechanics of conversion are not intuitive yet, how a post-money SAFE converts at your priced round walks the arithmetic, and it applies identically here. The bridge is just another SAFE in the stack, and it converts alongside the rest.

The cap is the negotiation

On a bridge, the cap is where the money is. The discount is nearly decorative by comparison, and founders spend their energy on the wrong one.

Go back to the worked example. A $2M SAFE at a $15M cap with a 20 percent discount, converting into a Series A at a $20M pre-money. The cap implies a $15M price. The discount implies $16M. The holder takes the lower, so the cap governs and the discount never binds.

That is the normal case, not an edge case. Whenever your next round prices above roughly the cap divided by one minus the discount, the cap sets the price and the discount is irrelevant. At a 20 percent discount, that crossover is about $18.75M. Price your Series A above that and the discount you negotiated hard has done nothing.

So the questions in order:

What cap? Every dollar below your last post-money is ownership you hand over. A cap near your prior post-money is the neutral read your next investor wants to see. A cap well under it is you repricing your own company downward without being asked to.

What discount? Set it, do not fight over it. In a world where the cap governs, the discount only matters if your Series A prices low, which is the scenario where you have bigger problems.

How much? The smallest number that reaches the milestone. Bridge dilution scales roughly linearly with size at a fixed cap, so an extra $500K of comfort is not free comfort. It is ownership.

The founder who capped their convertible at €1M rather than take €1.5M understood exactly this. They were not turning down money. They were declining to sell more of the company than the milestone required.

Three things your next investor reads

This is the most useful thing in Spectup's piece and the part founders never plan for. Series A investors scrutinize a bridge along three dimensions, and you control all three.

Who led it. Insider-led at a flat valuation reads positively. Outsider-led with a steep discount signals that your insiders declined to participate, which is the loudest negative signal on your cap table. If your existing investors are in, get that on the record.

The price. A cap near your prior post-money is neutral. A steep discount suggests your insiders are pricing in risk, and the next investor will ask what they know.

How long it bought. Six months is normal. Three months is concerning, because it says you will be raising again immediately. Twelve months suggests you raised prematurely, or that the Series A was never close.

Read those together and the strategy is obvious. A bridge that is insider-led, priced near the last round, and sized for about six months is nearly signal-free. One that is outsider-led at a 30 percent discount for three months tells a story you will spend your Series A meetings rebutting.

You are not just raising money. You are authoring an exhibit that every future investor will read.

Size it against a milestone, not a gap

The failure mode is sizing the bridge against the hole in your bank account. Founders compute months of runway missing, raise that, and call it a plan.

Size it against the proof that earns the round. The bridge has to buy a specific, nameable milestone that changes an investor's answer. Not more time. A number that moves, a customer cohort that renews, a model that works. Same logic as sizing the original round, which is why how much to raise at pre-seed and how much runway you need and the milestones that earn the next round are the right places to start.

Spectup's timing point is the tell: bridges work best for startups needing two or three months to finalize a Series A, as opposed to twelve months of general support. If you need twelve months of support, you do not have a bridge situation. You have a company that is not fundable at the moment, and a bridge does not fix that. It postpones the same conversation with less ownership left.

When not to raise one

If you cannot name the milestone, do not raise the bridge. Cut burn instead.

That is an unpopular sentence, and it is the honest one. A bridge that funds general runway converts a hard conversation today into the same hard conversation in six months, at a worse valuation, with 5 or 6 points less ownership, and now with a bridge on your cap table that your next investor will read as a runway operation. You paid for the privilege of a worse position.

The diagnostic question: what is true in six months that is not true today, and does it change an investor's answer? If you cannot say it in one sentence with a number in it, the problem is not capital. If your round has been out for months and nothing is landing, the issue is usually upstream of runway, and why your pre-seed keeps getting passed is the more useful place to look than a bridge deck.

Bridges are not a mark against you anymore. But they are still the most expensive time you will ever buy, and they are only worth it when you know exactly what you are buying. Knowing the number before you take the money is the entire job, and it is what The Funding Framework is about.