Email Address Policies
Configure email address policies that automatically generate and assign email addresses to mailboxes based on user attributes. Policies define the format of primary and alias SMTP addresses for your organization.
Note: In Exchange Online, email address policies are simplified compared to on-premises Exchange. The default policy assigns addresses based on the user’s alias and the default domain.
Email Address Policy List
| Column | Description |
|---|---|
| Policy Name | Display name of the policy |
| Priority | Processing order |
| Address Format | Template for generating addresses |
| Applied To | Users, groups, or filter criteria |
| Status | Applied or pending |
Address Format Templates
Common Formats
| Format | Example | Template |
|---|---|---|
| First.Last | john.smith@company.com | %g.%s@domain |
| FirstLast | johnsmith@company.com | %g%s@domain |
| First.LastInitial | john.s@company.com | %g.%1s@domain |
| FirstInitial.Last | j.smith@company.com | %1g.%s@domain |
| First_Last | john_smith@company.com | %g_%s@domain |
Template Variables
| Variable | Description | Example |
|---|---|---|
| %g | Given name (first name) | John |
| %s | Surname (last name) | Smith |
| %1g | First character of given name | J |
| %1s | First character of surname | S |
| %d | Display name | John Smith |
| %m | Alias | jsmith |
Default Policy
The default email address policy applies to all new mailboxes:
- Uses alias@defaultdomain.com format
- Applied when no other policy matches
- Cannot be deleted (but can be modified)
- Lowest priority (applied last)
Creating Custom Policy
- Name the policy — Provide a descriptive name.
- Define format — Select or create the email address format template.
- Set filter — Define which users the policy applies to (department, location, etc.).
- Set priority — Position relative to other policies.
- Apply — Activate the policy and generate addresses.
Multi-Domain Policies
For organizations with multiple domains:
- Create separate policies per domain
- Filter by department, location, or custom attribute
- Assign different primary domains to different user groups
- Add alias addresses from additional domains
Best Practices
- Use consistent format — Apply the same address format organization-wide for professionalism.
- Plan for duplicates — Define a process for handling name conflicts (e.g., john.smith2@).
- Test with pilot group — Apply new policies to a small group first.
- Document policies — Record which format and filter is used for each policy.
API Reference
GET /api/exchange/email-address-policies
List email address policies
POST /api/exchange/email-address-policies
Create email address policy
PUT /api/exchange/email-address-policies/:id
Update policy
POST /api/exchange/email-address-policies/:id/apply
Apply policy to matching recipients