Calculated Custom License Examples for MSP Billing

Calculated custom licenses are best used when an MSP billing quantity needs service logic, filters, inclusions, exclusions, or overage calculations.

Use a standard custom license for copying a Microsoft License SKU or Subscription that has no complexity. Use calculated custom licenses for the recurring services MSPs actually bundle, include, exclude, and bill as add-ons.

1. Bill managed users automatically

Billing problem: You bill the client per managed user, but the number changes as users start, leave, or become disabled.

Example calculation: All users, filtered to active licensed users. Enable Exclude disabled users and Only licensed users.

Useful filters: Domain, department, office, location, company name, user type, assigned license SKU.

PSA result: Map the calculated custom license to the managed-user service item.

2. Bill managed-user variations

Billing problem: A client has different managed-service plans for different user groups, such as Basic, Standard, Premium, onsite staff, franchise users, or users in a specific office.

Example calculation: Active licensed users filtered by selected Microsoft license SKUs, department, office, location, company, or domain.

Example: Business Premium + E3 + E5 users, filtered to the London office, with duplicate users removed.

PSA result: Map each calculated custom license to the correct managed-user plan in the PSA.

3. Bill add-on overages outside the managed-user plan

Billing problem: A service is included for managed users, but the customer has extra users or mailboxes that also consume the service.

Example calculation: Add-on user count minus Managed Users custom license.

Example services: Email security, spam filtering, cloud backup, signature management, endpoint tools, security awareness, archiving, or compliance add-ons.

PSA result: Bill only the add-on users not already covered by the managed-user bundle.

4. Bill mailbox backup overages

Billing problem: Mailbox backup is included for managed users, but the tenant has extra shared mailboxes, service mailboxes, or non-managed mailboxes that still need backup billing.

Recommended setup:

• Create a custom license that counts user and/or shared mailboxes for backup.
• Create or reuse the custom license that represents managed users or managed-user included mailboxes.
• Create a calculated custom license: Mailbox Backup Count minus Managed Users / Included Mailbox Count.

PSA result: Bill only the mailbox backup overage outside the managed-user agreement.

5. Bill spam filtering or email security

Billing problem: Email security applies to protected mailboxes, but some of those mailboxes may already be included under managed-user billing.

Example calculation: Protected mailbox count minus Managed Users custom license, or protected mailbox count filtered by domain, department, company, or location.

PSA result: Bill spam filtering/email security accurately without manually comparing mailbox counts to managed-user counts.

6. Bundle multiple Microsoft SKUs into one service item

Billing problem: A managed service applies to users with several possible Microsoft licenses, but you want one PSA billing line.

Example calculation: Business Premium users + E3 users + E5 users, with Remove duplicate users enabled.

Optional filters: Only include users from a specific office, department, company, or domain.

PSA result: One managed service or add-on item receives the combined user count.

7. Split one tenant across companies, departments, or locations

Billing problem: One Microsoft tenant contains multiple billing entities, franchises, locations, or departments.

Example calculation: Active licensed users where domain equals franchiseA.com, department equals Finance, office equals London, or company equals a specific entity.

PSA result: Create separate calculated custom licenses and map them to the correct PSA company, agreement, or billing line.

8. Bill signature management

Billing problem: Signature management may apply only to users in a specific Entra ID group or only to users outside a managed-user inclusion.

Example calculation: Signature group users, optionally minus Managed Users custom license if signatures are included for managed users.

PSA result: Bill only the users who should be charged for signature management.

9. Bill cloud add-on bundles

Billing problem: You sell a cloud add-on bundle made up of backup, email security, archiving, or other per-user tools.

Example calculation: Backup users + email security users + archiving users, with duplicate users removed where the bundle should count each user once.

PSA result: One bundle billing line instead of multiple manual count checks.

10. Bill users selected by extension attributes

Billing problem: The normal Microsoft fields do not identify who should be billed for a service.

Example calculation: Active licensed users where extensionAttribute1 equals Managed, Backup, Security, Premium, or another agreed billing flag.

PSA result: Gives the MSP a controlled way to bill only the users marked for that service.

Setup advice

1. Start with the client agreement: what service is included, and what should be billed as extra?
2. Create simple custom licenses for the base counts, such as managed users or mailbox backup count.
3. Use calculated custom licenses to subtract included services from wider add-on counts.
4. Use filters when the customer has separate billing groups inside one tenant or needs to filter for counts.
5. Check the calculated result before mapping it to the PSA.