Written by Craig D. Robins, Esq.
The instant a bankruptcy petition is filed, an “automatic bankruptcy stay” goes into effect, making it illegal under federal law for creditors to take any further steps to collect on a debt. This is the first step to getting debt relief in any bankruptcy case.
So who notifies the bill collectors and creditors about the bankruptcy filing, and how do they find out that you filed for bankruptcy? I previously wrote: How Quick Will Creditors Stop Calling Me If I File Bankruptcy? 
Once the bankruptcy petition is filed with the bankruptcy court, the Court sends out a “Notice of Commencement” form which, in a Chapter 7 case, is also known as a “Notice of Chapter 7 Case, Meeting of Creditors and Deadlines.”
This notice is uniform throughout the country as it is on Official Form 9A. The court typically mails the notice between two and four days after the petition is filed.
The Court sends the notice to all creditors and interested parties listed in the petition. Thus, it is important to make sure that you provide correct and accurate addresses for all creditors in the petition.
The notice contains your name and address; your Social Security number; the date of filing; the name and address of the bankruptcy court where the case is pending; the chapter of bankruptcy you filed for relief under (usually Chapter 7 or Chapter 13); the name of the judge; the name, address and phone number of the trustee; the date, time and location for the meeting of creditors; the deadline for filing objections to discharge; the deadline for filing objections to exemptions; a notation as to whether a “presumption of abuse” exists (in Chapter 7 cases); a notice to creditors that they may not engage in collection actions; and a schedule of explanations of common bankruptcy terms and concepts.
This notice is the only time the Court will send a creditor any documentation containing your Social Security number.
Violating the automatic bankruptcy stay is a very serious offense. What Are Your Rights If a Creditor Violates the Automatic Bankruptcy Stay? 
If creditors call you after filing because they have not yet received this notice, you can tell them that you filed for bankruptcy and give them the chapter (usually 7 or 13), the case number, and the name of the Court. For most of my clients that would be “the Bankruptcy Court for the Eastern District of New York.”