Print out and fill out the application form. You should fill out the C1 form if you're age 16 or older and the C2 form if you're under 16. Complete all sections using all capital letters. You can download these forms from the "Passport" forms section of the UK in the USA website (see Resources below).
Have two passport photos taken. The photos must comply with the Home Office Identity and Passport Services requirements (see Resources).
You will have to send a fee with the application. Check the UK in the USA website to for the latest fees. Fees may be paid by Mastercard or Visa. If paying by credit card, print, complete and sign the credit card authorization form available on the "Fees" section of the UK in the USA website. You may also pay by money order, cashier's check or certified bank check made out to British Embassy Government Account. The UK Consulate does not accept personal checks as payment.
Mail your completed application form, fee and postage payment, two passport photographs and your UK passport to: The UK Passport Service for the Americas and Caribbean British Embassy 19 Observatory Circle, NW Washington, DC 20008
You may check the status of your application by filling out the online status inquiry form on the UK in the USA website, or by calling the passport helpline. Numbers for the passport helplines are listed in the "Contact Us" section of the UK in the USA website.