How to write a kill fee clause that protects both sides

A project cancelled midway through leaves real costs behind, time already spent, capacity that was reserved and can't be easily reallocated, and a missing kill fee clause leaves those costs entirely unaddressed. A clause that's vague or absent turns every real cancellation into an improvised, uncomfortable negotiation.

A kill fee clause that's actually fair isn't punitive. It's specific enough that both sides know what happens before a cancellation is ever on the table.

A cancelled project leaves real costs on the table if nothing addresses them

Work already completed, time already reserved, and capacity that can't be instantly reallocated are real costs regardless of why a project ends early. A missing clause doesn't remove those costs, it just leaves them undefined until a cancellation forces an uncomfortable conversation about who absorbs them.

Scale the fee to when in the project cancellation actually happens

A cancellation in week one carries different real costs than one in week ten, and a flat fee regardless of timing is fair to neither side depending on when it lands. Scale the fee to project stage, a percentage tied to milestones or elapsed time, rather than one fixed number.

Separate recovering sunk cost from compensating for lost opportunity

A kill fee that only covers work already done is different from one that also compensates for reserved capacity that couldn't be filled elsewhere, and conflating the two makes the number harder to justify. Be explicit about which the fee is actually covering, or both, and why.

Name what happens to work already in progress at the time of cancellation

Define explicitly whether the client receives partial deliverables completed up to the cancellation point, and under what terms. Leaving this undefined turns a straightforward cancellation into a separate dispute about ownership of unfinished work.

Explain the clause before it's ever needed, not in the middle of a cancellation

Walking a client through the kill fee clause for the first time during an actual cancellation reads as a surprise, even when it was in the signed contract. Briefly explain the reasoning behind it at signing, so it's understood as a standard practice, not a penalty invented in the moment.

A simple checklist

If you do nothing else, do these five things:

• Scale the fee to project stage, not one flat number.
• Be explicit about whether it covers sunk cost, lost opportunity, or both.
• Define what happens to partial deliverables at cancellation.
• Explain the clause at signing, not for the first time during a cancellation.
• Base the fee on real tracked progress, not an estimate from memory.

Do that, and a kill fee clause becomes a fair, expected part of the agreement, not an ugly surprise sprung during an already difficult conversation.