To pay for priority service fee of $150.00 please click on the following link and follow the steps below:
Link: https://www.visainfoservices.com
After following the link, click on the "Select Country" option and choose "United States" as the country where you are traveling from. This will direct you to the Official UK visa Application Website in the United States.
Once you’re on that page, scroll down to the "Additional services options" which are highlighted in blue. Click on Priority service.
When you’ve clicked Priority Service a list of "How to apply" instructions will show. In step 2, click on the highlighted "Products & Services" page link.
On the "Designated UK Border Agency visa section" choose UKBA New York Visa Section
Next to Priority Service, click Add to Cart. You will be directed to your Cart Checkout for the priority service payment. Please have your Visa Application Number (GWF Number) ready along with your credit card information.