What a Bridge Round Is and When It Makes Financial Sense

A bridge round is a funding mechanism that provides additional capital to extend a company's runway between two priced equity rounds. It is typically structured as a convertible note or a SAFE with terms that convert at the next priced round. The bridge is not a standalone round with its own valuation negotiation. It is capital provided by existing investors, or occasionally new investors, to allow the company to reach a milestone that justifies the next priced round at better terms.

The Distinction That Matters

A bridge round makes financial sense only when a specific, near-term milestone will materially improve the terms of the next priced round — a revenue threshold, a product launch, a regulatory approval, or a significant customer signing. A bridge round taken without a clear milestone attached to it is not a bridge to better terms. It is additional dilution taken at uncertain pricing, which extends the runway without changing the company's negotiating position.

The financial model must quantify what the bridge enables. If the bridge funds three months of operations that take the company from £400,000 ARR to £700,000 ARR, and the Series A revenue multiple for the sector implies a materially higher valuation at £700,000 than at £400,000, the dilution from the bridge is justified by the valuation improvement it enables. If the bridge funds three months of operations with no clear milestone attached, the dilution is taken without the corresponding benefit.

Why It Surfaces in a Raise Process

A bridge round that converts as part of a subsequent priced round adds to the outstanding convertible instruments that must be modeled in the fully diluted cap table. The bridge note's conversion mechanics — cap, discount, and interest accrued from the bridge date — must be reflected in the cap table before the priced round term sheet economics are evaluated.

The Common Structural Error

The most common error is taking a bridge round to avoid a down round without modeling whether the bridge actually solves the underlying problem. A company with six months of runway that takes a three month bridge and reaches the end of that bridge without hitting the milestone still faces the same valuation conversation with three fewer months of runway and additional converting instruments on the cap table.

RELATED TERMS
- What a Convertible Note Maturity Date Means for a Startup Cap Table
- How a SAFE Note Converts at a Valuation Cap
- How a Startup's Net Burn Rate Is Calculated
- Cap Table Errors That Surface During Legal Due Diligence and the Infrastructure Required to Resolve Them

Tool: Startup Financial Readiness Scorecard