Convertible loan vs equity: what impact founders should really weigh

Convertible loan or a priced equity round? This question shows up in almost every first financing – and for impact startups in Germany's rural ecosystem it is far more than a formality. It decides how much mission and control founders still hold after the round.

This guide compares both instruments along the dimensions that actually matter in practice – including the mission-lock clauses we regularly see in term sheets at Founders Bay.

Table of contents

• Both instruments in one sentence
• When a convertible loan makes sense
• When a priced equity round makes sense
• Dilution compared
• Mission-lock: the underrated factor
• Common pitfalls
• FAQ

Both instruments in one sentence

• Convertible loan: a loan that converts into shares at the next qualified financing event – usually with a discount and/or a cap.
• Priced equity round: investors immediately receive shares, typically voting preferred shares with their own clause stack.

Signing a convertible loan mainly defers the valuation and the clause stack – it does not reduce their weight.

When a convertible loan makes sense

Often the right tool when:

• the valuation is still too fragile to negotiate cleanly,
• you need a bridge to the next round (3–12 months),
• business angels want to move fast without a 30-page agreement,
• a future lead investor is already lined up but won't formalise yet.

Upside: low transaction cost, fast execution, no immediate cap-table fight. Downside: until conversion the loan is debt, with repayment and interest obligations if the next round never happens.

When a priced equity round makes sense

Typically the right tool when:

• a lead investor with a clear ticket and reporting expectations is on board,
• the valuation is defensible (traction, pipeline, comparables),
• the round needs to fund pilot projects with the German SME sector that run for several quarters,
• public co-investors like HTGF or regional funds require equity structures.

Upside: clean cap table, aligned governance, no refinancing risk from a non-converting loan. Downside: longer negotiation, higher legal cost, immediate dilution.

Dilution compared

Both instruments dilute – just in different places.

• A capped convertible converts at the lower of cap or next-round valuation, often with a 15–25% discount on top. In a strong next round this can mean materially more shares than founders initially modelled.
• A priced round dilutes immediately, but the dilution is fully negotiated and final. Stack three or four convertibles on top of each other and the cumulative dilution at conversion can easily exceed what a priced round would have cost.

Rule of thumb: with three or more convertibles in the cap table, run a cap-table stress test before signing the next one.

Mission-lock: the underrated factor

For impact startups the decisive question is not "convertible or equity?", but: which instrument carries our mission through the next few years?

The clauses that matter most in practice:

• Reserved matters / mission-lock: which decisions (exit, pivot, new business lines) require which majority? Convertibles often only regulate this at conversion – priced rounds bind it immediately.
• Drag-along: above which majority can shares be force-sold? A drag threshold set too low can dismantle a mission-driven strategy overnight.
• Liquidation preference: 1x non-participating is market standard. Anything above shifts exit proceeds so strongly toward the investor that founders – and any impact reinvestment – may walk away with nothing on a moderate exit.
• Vesting & founder replacement: who holds the mission if a founder leaves? This question belongs in both instruments.

At Founders Bay we recommend anchoring mission-lock clauses in the main agreement – never in a side letter that silently expires with the next investor.

Common pitfalls

1. Underestimating interest: an 8% convertible over 18 months adds ~12% to the conversion amount – meaningful extra dilution.

2. Setting the cap too low: an attractive cap today can cost 10–20% of equity if the next round prices much higher.

3. Overlooking the MFN clause: later investors automatically inherit the best terms – including a lower cap.

4. Mission-lock only in the pitch: if the mission isn't in the contract, it doesn't bind on exit.

5. Forgetting public loans: if KfW or regional grants run in parallel, conversion mechanics must be properly synchronised.

Key takeaways

• Convertibles are fast and lean – but they postpone dilution, not its magnitude.
• Priced rounds force clarity early and are often the more honest instrument once a round is large enough.
• For impact startups, what decides outcomes is not the instrument but the clause stack on mission, drag-along and liquidation preference.
• Stress-test every term sheet across at least three exit scenarios before signing.

How Founders Bay supports

At Founders Bay we walk founders from Germany's rural ecosystem through exactly this decision – in a 6-month program, with warm investor intros and 150+ mentors. Free of charge, no equity.

Want a second pair of eyes on your first term sheet? Apply for Batch 9.

FAQ

What is the difference between a convertible loan and equity?

A convertible loan is initially debt and converts into shares at the next qualified financing event – usually with a discount and/or a cap. A priced equity round transfers shares immediately, typically preferred shares with their own clause stack.

What is a cap on a convertible?

The cap is a maximum valuation at which the loan will convert. If the next round prices above the cap, convertible holders benefit disproportionately – conversion happens at the lower cap valuation.

Does a convertible dilute more than a priced round?

A single one usually less, because pricing is deferred. In aggregate often more, especially when several convertibles with discount and cap are stacked and convert at the same time.

What does mission-lock actually mean?

Mission-lock refers to contractual mechanisms (reserved matters, qualified majorities, veto rights) that ensure the mission of the startup cannot be changed without founder or mission-board approval.

Which instrument is better for impact startups?

There is no universal answer. What matters is not the instrument itself but how drag-along, liquidation preference and mission-lock clauses are drafted. A well-negotiated convertible can be more mission-safe than a poorly negotiated equity round.

When should founders involve lawyers?

At the term-sheet stage at the latest – ideally already when setting the cap. Negotiation leverage is highest before signing.