Drone supports Github and Bitbucket organizations out of the box. There is no extra setup. There are no additional fees. When creating a new project you will see a list of all your repositories, both individual and organization.
Team Billing
If you work in a team setting, you may want to setup a single paid plan for you and your team members. Once you purchase a plan, you will have the option to link your Github and Bitbucket organizations to your account:
Once linked, your team members will be able to setup private projects owned by (or forked from) these organizations. These projects will be counted against your plan and quota.
NOTE: Your team members will not be able to modify or administer your plan