Use SharePoint as a business-to-business (B2B) extranet solution
An extranet site in Microsoft SharePoint 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 Microsoft 365, partners connect directly to a members-only site in SharePoint, without access to your on-premises environment or any other SharePoint sites. Microsoft 365 extranet sites can be accessed anywhere there's an Internet connection.
Depending on your collaboration needs, you can include Microsoft 365 groups or Microsoft Teams as part of your extranet.
Why use Microsoft 365 for a B2B extranet?
Time-to-value and Cost savings: a Microsoft 365 B2B extranet eliminates the need for creating a costly on-premises extranet sites. No additional hardware is required and using Microsoft 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: Microsoft 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 Microsoft 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. Microsoft 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.
Compare Microsoft 365 extranet with a traditional SharePoint on-premises extranet
|Condition||Microsoft 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 Microsoft 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 Microsoft 365 sites functionality||Often requires custom solutions/apps|
To get started setting up a SharePoint extranet site:
Read Create a B2B extranet with managed guests if you want to delegate guest access management to specific approvers in either your organization or the partner organization.
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.