Series A timelines slip. A lead investor goes quiet, a market shift spooks your target funds, or diligence drags past the point where your runway can wait. When that happens, a bridge round is often the right move, but only if you structure it carefully. A poorly negotiated bridge can crater your cap table, signal desperation to new investors, or lock you into terms that haunt you at the next round.
Here is how to do it right.
Decide Whether You Actually Need a Bridge
Before you draft a single term sheet, be honest about why the Series A slipped. If the delay is logistical (a lead partner is on leave, a competing deal is slowing their timeline), a bridge makes sense. If the delay is because investors are unconvinced by your metrics, raising more capital on the same story is not a fix. A bridge in that scenario just delays a harder conversation and burns more of your existing investors' goodwill.
Run a hard look at your numbers. If you have less than four months of runway and a credible path to closing a Series A within nine to twelve months, a bridge is worth pursuing. If neither of those conditions is true, you may need to consider a different path entirely, whether that is a down round, a pivot, or a controlled wind-down.
Talk to Your Existing Investors First
Your current cap table is your first call list. Existing investors already know your business, have a financial incentive to protect their position, and can move faster than a cold lead. Reach out to your most engaged angels and your pre-seed or seed fund before you approach anyone new.
Be direct about the situation. Tell them the Series A timeline has moved, tell them how much runway you have, and tell them exactly what milestone closing a bridge will let you reach. Vague asks get vague responses. A specific ask, for example, "We need $400K to get us to $80K MRR, which is the threshold our Series A lead has tied to a term sheet," gives investors something concrete to evaluate.
If existing investors are unwilling to participate, treat that as signal. It does not necessarily mean the company is broken, but it means you should understand their reasoning before you go wider.
Choose the Right Instrument
Most bridge rounds use either a SAFE (Simple Agreement for Future Equity) or a convertible note. Both defer the valuation conversation to the next priced round, which is the right call when your leverage is limited and you are not in a position to negotiate a fair price.
The key terms to focus on are the valuation cap, the discount rate, and whether you include an MFN (most favored nation) clause.
For a bridge into a Series A, a discount of 15 to 20 percent on the next round is standard. A valuation cap should reflect a modest premium to your last round, not a leap that will create painful dilution when the Series A prices. If your seed round was capped at $8 million, a bridge cap somewhere between $10 million and $13 million is a reasonable range depending on your traction.
Avoid adding warrants or interest rates above 8 percent if you can. These terms compound the dilution problem and make your cap table harder to explain to Series A investors doing diligence.
Set a Hard Close Date
Bridge rounds have a way of drifting. An investor says they are in, then asks for another week, then another. Meanwhile your runway is shrinking. Set a close date when you open the round, typically 30 to 45 days out, and hold to it. Tell investors the round closes on a specific date regardless of whether it is oversubscribed.
A deadline creates urgency without pressure. It also gives you a clean story: you raised a $500K bridge in six weeks from existing investors and one new strategic angel. That is a much better narrative than a rolling close that took five months.
If you hit your target early, close early. Do not keep the round open hoping for more. Overshooting is fine, but an indefinite close signals that you are struggling to raise.
Use the Capital to Hit One Specific Milestone
The worst bridge rounds are raised to "extend runway." That framing tells Series A investors that you spent money without generating a meaningful result. The best bridge rounds are raised to hit a specific, measurable milestone that unlocks the next institutional check.
Before you close, define that milestone in writing. It might be reaching a revenue number, signing two enterprise contracts, completing a product integration, or hitting a retention benchmark. Whatever it is, tie your bridge narrative to it. When you go back to Series A investors, you will be able to say: we raised a bridge, we hit the milestone we promised, and here are the numbers.
That is a story investors can fund.
Watch the Pro Rata and Information Rights
When you bring new investors into a bridge, be careful about what rights you hand out. Pro rata rights for small check sizes (under $50K) create administrative headaches at your Series A and can spook institutional leads who want clean cap tables. Information rights are appropriate for larger checks but should be limited in scope.
Review your existing investor agreements before you add new terms. Some seed-stage SAFEs include MFN clauses that require you to extend the same terms to earlier investors if you offer better terms to new ones. Missing this can create legal issues at closing.
The Honest Takeaway
A bridge round is a tool, not a strategy. Use it to buy yourself a defined window to hit a concrete milestone, and be transparent with every investor about exactly why you need it and what it will accomplish. Founders who treat a bridge as a patch on a leaking boat rarely end up in a better position six months later. Founders who use it as a focused sprint to a specific goal often do.
Start with your existing investors this week. Have the honest conversation before you run the process.