External User Access to Office 365 Services

• Most Office 365 services permit users who are not licensed for a tenancy to access some of the tenant’s data.
• The features can help work with off-site contractors, business partners, and customers.
• The services can vary in the breadth of external access and granularity of access controls.
• To limit the risk of data leakage, organizations should plan and closely monitor external access.

External users are users who do not hold an Office 365 license within an organization, but who may be authorized to access some content or service within that organization’s Office 365 subscription. Microsoft allows organizations to make certain content within their tenancy accessible, in limited ways, to external users for free. Allowing external users can simplify collaboration with contractors, business partners, and customers. However, organizations might have to purchase licenses for individuals who would otherwise be designated as external users, if the free capabilities are insufficient.