When you claim email domains your members will only be able to accept Slack Connect invitations from domains you have claimed. This ensures that members can only accept Slack Connect invitations from the workspaces you manage.

1. From your desktop, click your workspace name in the sidebar.
   
2. Select Tools & settings, then click Workspace settings.
3. Select Email Domains in the left sidebar. If you don’t see the left sidebar, click  Menu in the top-left corner to find it.
4. Click Add Domain.
5. In the domain field, enter the domain (or wildcard domain) you’d like to verify, then click Next.
6. You'll need access to a Domain Name System (DNS) to confirm the domain belongs to your organization. Follow instructions provided by your domain hosting service to create a DNS TXT record (for Host, use @ if the domain is not a wildcard and _slack-challenge if it is). It may take up to 72 hours for changes to take effect.
7. After confirming your TXT record is added to your DNS, return to Email Domains on your Slack admin dashboard.
8. Next to a domain, select Verify domain in the status column, then click Next. If you'd like, set your org as the primary organization for Slack Connect.

When you verify and restrict email domains, you can choose to limit your members’ ability to join new workspaces in the following ways:

• Accepting Slack Connect invites
  Your members will only be able to accept Slack Connect invitations from domains you have claimed. This ensures that members can only accept Slack Connect invitations from the workspaces you manage.
  
  
• Joining external workspaces
  Members of other workspaces won’t be able to send invitations to email addresses on domains that your organization has claimed. If you claim a domain after an invitation has been sent, your members won’t be able to accept it.
  
  

1. From your desktop, click your organization name in the sidebar.
   
2. Select Tools & settings, then click Organization settings.
3. From the left sidebar, click  Security, then Email Domains.
4. Click Add Domains.
5. In the domain field, enter the domain (or wildcard domain) you’d like to verify.
6. Choose to apply domain claiming restrictions on joining external workspaces or accepting Slack Connect invitations, then click Next.
7. You'll need access to a Domain Name System (DNS) to confirm the domain belongs to your organization. Follow instructions provided by your domain hosting service to create a DNS TXT record (for Host, use @ if the domain is not a wildcard and _slack-challenge if it is). It may take up to 72 hours for changes to take effect.
8. After confirming your TXT record is added to your DNS, return to Email Domains on your Slack admin dashboard.
9. Next to a domain, select Verify domain in the status column, then click Next. If you'd like, set your org as the primary organization for Slack Connect.

Tip: You can also claim domains for your Enterprise org to prevent people from creating unsanctioned workspaces and make your org’s workspaces easier to find.