Nanny- real costs and flex?

[NewBallsPlease00]

Hi, I have 2 kids one at nursery ft and one at school with wrap care
I am wondering about a nanny a couple of days a week to try and make life more simple
I am hating the rush rush rush effect of ours mornings and evenings and a couple of days of later PJ, but can't afford nor would I choose FT nanny, so-
Does anyone else do this split arrangement (in time will be using free hours at nursery to subsidise that)
As a very rough idea what would actual cost of a nanny be, I get confused with gross net etc ie nursery is £50 day, £5 hour, so by time I've paid all the tax etc what would nanny equivalent be (mids) assuming 11 hour day x2 as hourly rate on Midlands location- say £12? I don't want to make enquiries if it's out of my league
Thanks

As a nanny who is currently looking for work, I see a lot of jobs being advertised as before/after nursery/school. Those are not very appealing. By paying for 11 hours per day, you make the job much more appealing.

Lets make some assumptions:
11 hours per day, 2 days per week. All year round (nanny would get at least 11.2 days of paid holiday, you could elect to decide when some of that occurred). £12 gross per hour... that may be realistic, you may find due to it being just 2 days that you would need to offer more to get the right candidates... but lets use £12 gross for now.
You will use a nanny payroll provider to do some of the admin, including the pension admin.
The job will involve driving a car... which the nanny is to provide... lets say an average mileage of 10 miles per day (keeps the maths easy).
There is an activity budget of £5 per day (reality may be that some days will incur more activity cost than others, especially during school holidays but this lets us average things out a bit).

11 hours x 2 days = 22 hours per week.
£12 gross per hour = £264 gross per week.
52 weeks = £13,728 gross per year.
Pensionable Pay (pay above qualifying earnings): £752
Employers pension contribution (at 2% of Qualifying Earnings, minimum rate for 2018/19 tax year): £157.04
Employers National Insurance: £767.83
Mileage (based on 92 worked days per year):£414
Activity budget (based on £5 per day 92 worked days per year): £460
Payroll and pension admin (monthly pay) yearly fee £240

Total cost to employer: £15,766.87

ALWAYS agree a gross pay rate. Nannies these days often have more than one job, so you cannot be certain that their personal tax allowance will be allocated to your role... plus with net pay agreements you pay the employee pension contribution in addition to the employer pension contribution which increases the cost even more... so agree gross pay, then your costs can be calculated in advance.

It depends on where you live, you might be able to find a nannyshare arrangement where the nanny would look after your two and one other family's children at the same time. That can almost halve the costs. There are websites which can help you find local families to share with.

Also, activity budget may vary e.g. If you live near a park, childrens centre or playgroups which are free or 50p you might be able to keep costs down.

Thanks very much, really helpful, nanny share might be doable, otherwise think it will be too far off.
Will look into it further now!