Can someone clarify childcare vouchers for me?

[Spedley]

You have to declare your weekly childcare costs and I don't know whether to include childcare vouchers from childcareplus?

https://www.gov.uk/childcare-costs-for-tax-credits
You cannot include the following in your childcare calculation:
* ...
* childcare vouchers in return for a reduction in your pay - this is called a ‘salary sacrifice’
* ...

My pay is reduced and I receive tax free vouchers instead, however I'm not certain that this is the same thing?
The website goes on to say that a 'salary sacrifice' is where you take a lower wage and vouchers instead. You then pay a lower tax rate and your employer pays less in national insurance.
This isn't what our vouchers are, we keep the same tax rate but receive the vouchers tax free. Royal Mail pays the same but the government gives us some of the tax back?

Does anyone know for sure?

[cloherty1976]

I have had the child care vouchers for years with the former voucher scheme kiddivouchers which I presume is the same. I used to buy the maximum allowed which is £243 a month and they take that off your gross salary so not to pay tax and national insurance. When applying you used to just give them your salary amount and that would tell them if you are eligible for vouchers. If you took the £243 a month it saves you about £80. It's £55 a week which saves you about £17