There are several steps you can take to stop collection calls. First of all, determine if they can be classified by harassment. While the law does not set the number of calls that you are allowed to receive from a particular creditor, it may be considered harassment if they are calling multiple times in an hour. Also, they are prohibited from calling you outside of an 8 A.M. to 9 P.M. window. Once again, your state may have more strict rules on this.
If your collection calls are annoying but not necessarily abusive, there are still measures you can take to limit the number of calls. First of all, let the collector know what times and telephone numbers are inconvenient for receiving the calls. For example, you can tell you that it is inconvenient to receive them at work or maybe in the morning if you work a late shift. Another step you can take that will at least temporarily stop the phone from ringing is to request verification of the debt. Once you have done that, preferably by certified mail, they will not be able to call you until they give you the verification requested.
Collection calls can be quite frustrating, but know that the federal government has taken steps to protect your peace from the harassment. Once you know your rights, you can handle collection calls.