Nanny with variable hours in term time and holidays

[JugglingChaotically]

We have been lucky enough to find a great nanny 4 days a week who is prepared to do 30 hours a week during term time and 40 hours a week during holidays with overtime as required for sick children, extra hours for parents work on occasions etc.
We have agreed a gross hourly rate. (Thanks for earlier advice on this nanny nick)
But I have no idea how to do the contract.
We can average out the rates (between term time and holidays) which is what I think the nanny will want, would be fair for holiday pay and would help her to budget but what happens if she leaves after a long stretch of term time and this has been overpaid?
What have others done in this situation?

I think you are best to contract for 30 hours plus extra
So normally you pay for 30 then in the hols you pay the extra hours worked

Thanks - I was just concerned that the nanny would prefer a salary that was averaged over the year to help her budget.

I know I would!

We have found averaging doesn't always work well. Holidays can be seen as "more work for the same pay" and so you might get the same amount of effort, just spread more thinly. If you are going to pay different rates it would be fair to pay holiday pay at an average rate rather than based on 30 hours basic, although the law may entitle you to use just the basic contracted hours.

Thanks for that. I do worry about extra hours for same pay being a little demotivating.
Can any parents or nannies help with their experience on this?

To be fair our experience was with hours that doubled in the holidays so it was a bigger ask.

JC - got your message will de-personalise my contract and send to you tomorrow

WA. Thanks. Appreciate it. No idea where to start and don't want to get it wrong and risk losing nanny.

Use a specialist nanny payroll agency - they will have a contract you can use.

MrA - thanks.
I use nannytax and did check but their std contract doesn't cover flexible pay, prorating or how to recover overpayments if the nanny leaves with a deficit of hours v cumulative pay.
I've had nannies for ages but really struggling with the varying hours concept.