You need to report nursery or child care vouchers if:
If you receive your nursery or child care vouchers in exchange for salary under the salary sacrifice scheme, you don't need to disclose this income on your tax return. This is because you don't pay Income Tax (or National Insurance contributions) on the vouchers under this scheme. This scheme is popular when you qualify within Statutory Maternity Pay.
If you don't receive your vouchers under the salary sacrifice scheme, the tax exemption for nursery or child care vouchers is £55 per week for any employee regardless of your earnings. If you receive more than £55 in vouchers you should add the excess amount to your gross pay from employment so that it can be taxed.