Use SharePoint Online as a business-to-business (B2B) extranet solution

An extranet site in SharePoint Online is a site that you create to let external partners have access to specific content, and to collaborate with them. Extranet sites are a way for partners to securely do business with your organization. The content for your partner is kept in one place and they have only the content and access they need. They don't need to email the documents back and forth or use tools that are not sanctioned by your IT department.

Traditionally, deploying a SharePoint on-premises extranet site involves complex configuration to establish security measures and governance, including granting access inside the corporate firewall, and expensive initial and on-going cost.

But with Office 365, partners connect directly to a members-only site in SharePoint Online, without access to your on-premises environment or any other SharePoint sites. Office 365 extranet sites can be accessed anywhere there's an Internet connection.

Depending on your collaboration needs, you can include Office 365 groups or Microsoft Teams as part of your extranet.

Why use Office 365 for a B2B extranet?

Time-to-value and Cost savings: An Office 365 B2B extranet eliminates the need for creating a costly on-premises extranet sites. No additional hardware is required and using Office 365 greatly reduces the resource and labor costs. Your IT department can focus on more important tasks than creating and maintaining extranet infrastructure.

Secure sharing: Office 365 B2B extranet provides a highly secure sharing experience with the IT governance and policies that you require, including:

  • The ability to protect yourself against accidental sharing by using owner-approved sharing through Office 365 groups or teams, which prevents users from inviting new users without approval.

  • The ability to restrict partner users to a single site or team. They cannot search for or view any content on sites or teams to which they have not been invited.

Seamless collaboration: Collaborate with your partner users as if they are part of your organization, including allowing them chat and conferencing through Teams.

Auditing and reporting. Office 365 B2B extranet offers visibility into the access of your content by external partner users. One of the key IT benefits is to be able to audit usage, including being able to see who is inviting whom and when an external user logs in to access the content. See Search the audit log in the Security & Compliance Center for more information.

Security and governance. Office 365 features such as data loss prevention and Microsoft Cloud App Security provide a robust feature set to help you create a secure guest sharing environment.

Compare Office 365 extranet with a traditional SharePoint on-premises extranet

Office 365 extranet
SharePoint "on-premises" extranet
Firewall access required for external users
No
Yes
Complex network and infrastructure configuration required
No
Yes
Security hardening
Managed through Office 365 configurations
Manually configured by IT staff
IT labor intensive
No
Yes
Ongoing maintenance needed
Minimal
Considerable
Additional hardware needed
No
Often
Controlling sharing experience for the extranet
Part of Office 365 sites functionality
Often requires custom solutions/apps

Get started

To get started setting up a SharePoint Online extranet site:

  1. Read Collaborate with guests in a site if you want to limit your extranet to a site with an Office 365 group, or Collaborate with guests in a team if you want to include a team.

  2. Read Limit accidental exposure to files when sharing with guests and Create a secure guest sharing environment to learn about options for securing your guest sharing environment.

See also

Microsoft 365 guest sharing settings reference