Can Zus be declared as a cost in Poland?

Having Just registered a business, I am now looking at what provisions I need to make to pay my tax and I am confused by how the system works. Because my business is very small I have an income which is eaten up by the large zus payment I am having to make, but I am unsure if in the company accounts this can be declared as a cost or not. Common sense would suggest yes but from vast experience, I know common sense and the Polish tax system don't go hand in hand

Yes - but the condition is that you must pay it on time. That means sending bank confirmation to your accountant.

Yes, but the calculations aren't quite 1zł to ZUS = 1zł in costs. If you don't know what you're doing, get an accountant - it'll cost you between 100-150zł+VAT a month for peace of mind, and you just throw your bank statements / receipts to the accountant at the end of the month and they'll tell you what to pay and when.

I do my own ZUS only on bank transfers,the cash is for me to keep

Isn't that tax evasion that could send you to prison ?

Everyone in Poland seems to do it.