it depend s if it is first party or third party collections. first party is the actual person you owe, the have access to the billing info. third party collectors do not have access to what you bought with your credit card. they know what you own plus interest and most times they just know the grand total because most "paper" as they call it, has been bought and sold and had interest and fees tacked on here and there so many times that the total owed is often times 1000%+ the original bill. best case scenario with a collector is be up front, you arent going to pay, just tell them straight out, they appreciate the honesty and not having to waste their time and yours calling every few days about whether that loan from granny has posted yet.lo.l