Obtain an Application for Replacement Naturalization/Citizenship Document, Form N-565, from U.S. Citizenship and Immigration Services. Complete Part 1 of the form. You need your name, address, date and county of birth, your original citizenship certificate number, phone number and "A" number. An "A" number is your Alien Registration Number; you may have had this assigned to you during the immigration process. Enter "None" if you don't have an "A" number.
Complete Part 2. Check "New Certificate of Citizenship" box in Section 1. Check the "My name has been changed" box in Section 2, "Basis for Application."
Complete the top and middle sections of Part 3. Check the correct boxes for your gender and marital status. Enter your height in feet and inches in the "Height" section. Enter the information regarding your last issued certificate. You need the issuing court or office's name, issue date and your name as shown on the certificate.
Indicate whether you've lost your citizenship at the end of Part 3. If you have, attach a paper explaining when you lost your citizenship, why you lost it and the resolution of the situation. List any actions USCIS took regarding your lost citizenship.
Complete Part 4. Check off the correct reason for your name change: marital action or court order. Enter the date of the marital action or court order on the line next to the box you checked. Skip Parts 5 and 6.
Sign and date the form if you're filing the form in a USCIS office in the United States. Don't sign if you're filling in an office in another country. You must sign the document in front of an USCIS officer or consular official if you're filling the form in a foreign USCIS office. Skip Part 8.
Get a copy of the marriage action or court order that shows your name change from the issuing court. Get a divorce decree or marriage certificate for marital actions. Ordinary photocopies are acceptable. Attach the copy to the back of the form along with your original citizenship certificate.
Have two color photos of yourself taken. Plan ahead. The photos must be less than 30 days old on the day you file the form. Go to a local store that offers passport photos. Photos must show your face in a frontal view, be passport-sized — 2-inches-by-2-inches — and on a white or off-white background. The height of your head, as measured on the photo from top of hair to bottom of chin, must be at least 1 inch but no longer than 1.38 inches. Your eyes must be positioned at 1.12 to 1.38 inches from the bottom of the photo. Don't wear anything on your head. Print your current name and "A" number -- if any -- in pencil or felt pen on the back of both photos.
Prepare the filling fee payment; the fee is $345 at the time of publication. Use a check or money order drawn off a U.S. bank and in U.S. currency. Make the payment to "U.S. Department of Homeland Security."
Mail the form, photos and fee payment to the USCIS office for your state of residence. Go to the official website of the USCIS to locate the correct office.