You need to grant Billing Management access to an IAM Group on AWS. After completing the official tutorial, the group still can not access Billing.
If that's your scenario, steps 1, 2, and 3 should be enough.
- On the top right, click on your user name, then My Account:
2. Search for IAM User and Role Access to Billing Information. Click edit:
3. Check Activate IAM Access and click Update:
4. On IAM > Policies, create a policy based on the Billing Service. Grant Read and Write access as you see fit:
5. Attach the policy to the target IAM User Group:
That's it. Your group now can manage Billing for you.
For more details on steps 4 and 5, check the official tutorial.