Most planners think of the contract as protection for the worst case. It is far more useful than that: it is the document that stops ordinary disagreements from turning into bad ones, because both sides already agreed what happens.

Scope, and what is excluded

State what you are doing. Then state what you are not. The exclusions feel awkward to write and they are the single most valuable paragraph in the document.

The fee and the payment schedule

Not just the total. The deposit, each instalment, the amount and the date each falls due. Vague payment terms are how a planner ends up several months of work ahead of the last payment received.

Cancellation, as a sliding scale

A booking canceled ten days out costs you a date you can no longer sell. One canceled ten months out costs you very little. Write it as dates and percentages rather than as “reasonable costs”, which nobody can agree the meaning of afterwards.

Postponement, separately

This is the clause most contracts are missing and the situation that comes up most. Say whether the fee carries to a new date, how long they have to choose one, and what you charge to replan around it.

Who books the suppliers

If the client contracts suppliers directly, a supplier failure is between them. If you contract on the client’s behalf, it is your problem. Both are workable. Being unclear about which one applies is not.

Changes of scope

Additions get priced, not absorbed. Without this clause, the difference between the client who adds two things and the client who adds twenty is entirely down to their personality.

Draft it from this structure and have somebody qualified in your jurisdiction read it once. The clauses local law is most likely to have an opinion about are liability and cancellation, and those are exactly the two you least want to get wrong.