Upvote:4
No. You have to apply online, pay the fee, then attend the appointment. https://www.gov.uk/government/publications/usa-apply-for-a-uk-visa/apply-for-a-uk-visa-in-the-usa Appointment slots only show in the online system after youβve submitted the application. Once booked, it is possible to change an appointment.
Itβs also possible to cancel an application and get the fee refunded, provided you do so before the appointment date.