Write down the specifics of when the passport went missing. Note the date, time of day and location where it was either lost or stolen. If your passport was stolen, try to remember physical characteristics of the person who stole it from you if you saw the person.
Go to a local police station to file a police report. Ask the police officer who takes your report for a copy of it.
Find the location of the nearest United States embassy or consulate. To obtain a replacement passport, you'll have to visit the office in person.
Get new passport photos taken. You'll need to bring these with you to the consulate or embassy to obtain a replacement passport.
Bring proof of your United States citizenship with you to the embassy or consulate. In most cases, a current driver's license, state-issued identification card or birth certificate copy is sufficient.
Complete the required paperwork to denote your passport as lost or stolen. An embassy or consulate official will then process the form for you.
Fill out paperwork for a new passport. Submit this form along with a copy of your police report and a copy of your old passport to the embassy or consulate official. You'll also need to give them your new passport photos as well as the applicable payment. In most cases, you'll receive a replacement passport that is valid for 1 year.