Tax free childcare topped up by 25%?

[Monkeypopcorn]

Second month topping up my tax free childcare account and the government side has topped it up by 25% not 20%.
I've kept the additional money in the account incase they come back for it but I'm so confused as to why this would have happened? I did a test £10 and got £2.50. Then did £400 last month and got £500. I've done the same again this month and it's happened again??

It's 20% of your bill so that is correct. You're doing the maths the wrong way around.

20% of 500 is 100 so they pay 100 and you pay the remaining 400 (80%).

They pay 20% of the total bill.
Which means if you put in 400, they put in 100. To make it to 500.

But it's much easier to just think of it as them adding 1/4 of what you put in.

Yes, it works the same as pension tax relief at source.

You pay in the net amount. Lets say £80. Government adds 25% of what you pay in £20. £20 is 20% of the total £100.

Ahh I've been an idiot, that makes sense now!
Next month will be a nice cheap month for me then now I can use the excess!!