When I want to add my customers to jira using SAML with Azure AD to have website acces so that they can use the service desk it would be nescesarry to buy Atlassian Access for all customers?
If so that will be costly because the do not use any other module.
Welcome to Atlassian Community!
When it comes to Atlassian access billing, only users who have access to products (licensed users) will count towards your bill.
For customers to use SSO, they must have an Atlassian account, which means that their accounts must be migrated from portal-only to Atlassian account so they are listed under Users (with internal licensed users), but customers don’t need a license to access the portal.
Will I pay for my Jira Service Management users?
Portal only customers will not be counted towards your Atlassian Access bill. If your portal only customers have an Atlassian account, any Atlassian Access features will be enabled for their account, however they'll not be a billable user for Atlassian Access unless they also have product access to another Atlassian Access supported product. Only Jira Service Management agents will be counted towards your Atlassian Access bill.
If you have any other questions regarding this matter, please let us know.