Can I be listed as a cosigner on a line of credit increase if I did not sign?

There is a law called the Statute of Frauds that requires any agreement to guaranty the debt of another to be in writing.  While the situation can have all kinds of exceptions, most of the time, a creditor cannot hold you responsible for the debts of someone else unless you have signed something.If the creditor tries to collect the debt from you, you may want to talk to an attorney who handles Collection Harassment cases under the Florida Consumer Collections Practices Act or the Federal Fair Debt Collections Practices Act (usually shortened to "FDCPA").  Most attorneys who handle such cases do not charge the client, as the statute allows the attorney to collect fees from the other side.