Hello @Yu-Jeong Seo,
What role/permission is required to enable “Allow Azure subscription users to view and optimize costs”?
That setting lives at the billing account (agreement) level, not at the subscription level. For Enterprise Agreement (EA/SCE) customers, you must be an Enterprise Administrator (EA admin) on the billing account to change it. Department Administrators or Account Owners cannot toggle this setting. For Microsoft Customer Agreement (MCA) customers, you need the Billing account owner or Billing account contributor role at the billing account scope.
Once enabled, what role is required to see the Cost Tab in the Subscription blade?
After the billing account setting is enabled, subscription-level RBAC controls access to cost data like Reader, Contributor, or Owner roles at the subscription level can all see the Cost tab. If you only want read access to costs (no ability to change resources), the Cost Management Reader role is the most precise. This is a built-in RBAC role designed specifically for cost visibility and this needs to be assigned at the subscription scope.
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