Legally, with that one and two child rate, your OT rate would be $36.33. You have to use a blending calculation for OT unless you want to postulate and document that the one child work is substantially different from the two child work. The idea being, You can't really say which 5 hours in the week are the OT hours, so to be fair you take 1.5 x the straight average, not times the lowest rate.

However that's pretty technical. Also, it has no implicitions for how the share partners agree to split the payments to the nanny.

We are doing a nanny share with another family and we each have 6 month old babies.

The other family needs only 40 hours per week. We would like 45.

Since there will only be 1 kid / 1 employer, how would we calculate OT?

Ideally I would like to specify a single child rate of 18/HR and a double child rate of 25. And the.mn our OT would be paid at 1.5x $18 or $27. Would this be acceptable to you, nannies? Other terms are standard (2 paid weeks of vacation 8 holidays and 6 sick days).