tuition fee payment time and visa problem for new undergrad

Hi guys. I'm an international student who has just received an unconditional offer. IC sent me an invoice that is due on 1-9-2014, but when am I supposed to settle the payment? Before or after making my visa application? I don't want to pay the full tuition when I still do not know whether I can actually get a visa and study there (although it shouldn't be a problem getting the visa). I want to pay the money after the visa is confirmed. Is this possible?

any help is appreciated