When you access the sign in page (https://www.familytreedna.com/sign-in) you are prompted to enter a Kit No. or GAP Username. Your account is identified by one of these two things, and cannot be changed once created.
What is a kit number?
Your kit number is used to identify your test and access your results. You do not need to create or register a kit number, it is automatically assigned when you order a test. It includes the contact information you entered when first ordering your test. Many aspects of your results and our database are identified by your kit number, and it is crucial for the processing and reporting your results. For this reason it cannot be changed once assigned.
What is a GAP Username?
GAP stands for Group Administrator Page, and is an interface used strictly by group project administrators to manage their project(s). To access the DNA results for yourself or a kit you manage, you will not have or need a GAP username; you'll access your results using your kit number and the password associated with your FamilyTreeDNA account.
An administrator can create a GAP username upon registering their GAP account, but it cannot be changed once created. It cannot contain special characters such as @, $, %, etc.
Can I have a single account for the kits I manage?
No. Each kit has a distinct kit number and cannot be combined with other kits. However, you can apply for a private group project to access the kits you manage through a single sign-on using a GAP username. You can learn more about this here.
Can I order additional testing for other individuals using the same kit number?
No. Whenever you order an add-on or upgrade while signed into a kit, the test you ordered is processed on the sample for that kit. If you wish to order a new test for a person, make sure you are not signed into a kit. If you manage multiple kits, make sure you are signed into the correct kit when placing your order. Submitting a DNA sample for two or more individuals under the same kit number is strictly prohibited to ensure accurate results.