The name change petition can be filed in the County Court or Supreme Court of the county where you live. The forms for changing a name or sex designation in the Supreme Court or New York City Civil Court are included in the chart below.Petitioner must be 19 years of age or older and must be a resident of Montgomery County to file a petition for a name change. The affidavit must be sworn before a notary public. The affidavit is available on the Maryland Department of Health's website. Name Changes for Minors​​ The applicant is required to serve this notice and file an affidavit of service with this Court. Use your current legal name to initial and sign these documents. Do I need documents or forms? To ask the court for a name change, you need to file a petition. Do I need documents or forms?