Looking at Tax Free Childcare it looks like you would get:
Childcare Cost:
Gross salary £37,401.18
Employers NI: £4,041.91
Payroll Admin: £200
Total childcare cost for claim: £41,643.09
Amount paid into each child fund: £8000
Government amount paid per child: £2000
Total: £30,000 (£2500 per month)
Parent pays nanny directly: £28,600
Therefore adjustment needs to occur...
Amount paid into each child fund: £7944
Government amount paid per child: £1588.80
Total per child: £9532.80
Nanny paid from account: £28,571.40
Parent pays nanny direct: £28.60
Parent pays Employers NI of: £4041.91
Parent pays payroll admin of £200
Cost to parent:
£7944 * 3 = 23,832 plus £28.60 + £4041.91 + £200 = £28,102.51
How exactly the scheme will work is unknown but this is based on what I know so far. With luck the child funds won't have to be of equal amounts, so it may be possible to do:
£8000 + £8000 + £7833 = £23,833 + 20% Government = £28,599.60
Cost to parent:
£23833 plus £0.40 + £4041.91 + £200 = £28,075.31
This scheme won't be operational for another year but is something to keep in mind.