Citizens of the United States, permanent residents and temporary working residents obtain nine-digit Social Security numbers by submitting an application along with relevant identification at an office of the Social Security Administration. Those who have lost their Social Security number cards apply for duplicate cards in the same way.
Social Security numbers cannot be applied for online. However, one can download an application for a Social Security number at the Social Security website, then mail or bring it in person to the local Social Security office along with originals or certified photocopies of required documents. Two separate pieces of photo identification are required. The preferred document to show proof of U.S. citizenship is a birth certificate. If this is not available, other documents that may be accepted include a U.S. passport, a U.S. hospital record of birth or a religious record indicating date of birth made before the fifth birthday. Primary documents to show proof of identity are a U.S. driver's license or a state-issued non-driver identification card. Other documents that may be accepted include a school identification card, an employee identification card, a health insurance card or a U.S. military identification card.
Since Social Security numbers are required to list children as dependants on tax forms, most parents obtain them for their children shortly after birth. Applicants who are 12 years and older when they request an original Social Security number card must come for an interview in person and produce evidence that they do not already have a Social Security number. This might include proof of long-term residency outside of the U.S., school records or tax records.