Email Aliases: Extra Addresses for One Mailbox

An alias is an extra email address for your mailbox. Mail sent to an alias lands in the same inbox as your primary address, no separate login or password needed.

For example, if your mailbox is john@company.com, you can add aliases like info@company.com, sales@company.com, or even john@company.net (if you own both domains). All messages arrive in the same place.

Why use aliases

• Professional presence: Use info@, sales@, support@ without creating separate mailboxes for each. This gives your business a polished look without the overhead of managing multiple inboxes.
• Multiple domains: Receive mail at name@company.com and name@company.net in one inbox. Ideal for businesses operating under multiple brands or domain extensions.
• Department addresses: Create billing@, press@, hello@ and route them all to the right person without dedicated mailboxes.
• Send from any alias: Reply as sales@company.com even though you log in as john@company.com. Recipients see the alias, not your personal address.
• No extra cost: Aliases are included in your plan. No per-address fees, no additional storage charges.
• Simple setup: An alias uses the DNS already configured for its domain. After saving, send a test message to confirm the address is receiving normally.

Real-world examples

Freelancer with multiple clients: You have one mailbox jane@janedesign.com. You add aliases for each client project, project-alpha@janedesign.com, project-beta@janedesign.com. All emails arrive in one place, and you can see which project an email was meant for via the Delivered-To header.

Small business with departments: Your team uses 5 mailboxes. Instead of creating separate info@, sales@, support@, billing@, and press@ mailboxes, you add them as aliases to the appropriate team member's mailbox. The office manager gets info@ and billing@, the sales lead gets sales@, etc.

Agency managing client domains: You manage clientA.com and clientB.com from one TrekMail account. A single mailbox ops@agency.com can have aliases contact@clientA.com and hello@clientB.com, all funneled into one inbox for efficient management.

Domain migration: You moved from oldcompany.com to newcompany.com but still receive email on the old domain. Add name@oldcompany.com as an alias to name@newcompany.com so nothing gets lost during the transition.

How aliases differ from mailboxes

When to use an alias: You want another address that goes to the same person's inbox. Common for role-based addresses (info@, sales@), brand domains, and temporary project addresses.

When to create a separate mailbox: You need a completely independent inbox with its own login, password, storage, filters, and forwarding rules. Common for individual team members and shared inboxes that multiple people access.

Who this is for

Where to find it

1. Go to Mailboxes.
2. Click Manage next to the mailbox.
3. Open the Aliases tab. Other tabs depend on the mailbox type, plan, and status:

You can also see how many aliases each mailbox has directly in the mailbox list, a badge like "+3 aliases" appears next to the address. Click it to jump to the Aliases tab.

Cross-domain aliases

If your account has multiple domains, you can create aliases on any of them. For example, if you own company.com and company.net, a mailbox at john@company.com can have an alias john@company.net.

This is useful for:

• Brand consolidation: One inbox receives mail from all your brand domains.
• Domain migrations: Keep receiving mail on old domains while you transition.
• Regional domains: info@company.co.uk and info@company.de both go to the same inbox.

Both domains must belong to your TrekMail account and be available for mailbox settings. You can prepare an alias while DNS is still being checked, but wait for the domain to show Active before relying on normal delivery. To send from an alias in webmail, its alias and domain must be active; the alias screen also shows a warning if that domain's DKIM setup is not ready.

How aliases interact with other features

Forwarding: If the parent mailbox has forwarding enabled, emails that arrive via an alias are forwarded too. The alias itself does not have its own forwarding rules. It inherits whatever the mailbox does.

Filters: Mail filters on the parent mailbox apply to all incoming mail, including messages addressed to aliases. You can create filters that match on the To header to sort alias mail into specific folders (e.g., move everything sent to sales@ into a "Sales" folder).

Catch-all: If a domain has catch-all enabled and you also have an alias on that domain, the alias takes priority. Mail to the alias goes to the alias target; mail to unknown addresses goes to the catch-all destination.

Auto-reply: The parent mailbox's vacation auto-reply applies to all incoming mail, including mail to aliases. There is no per-alias auto-reply in the current version.

Webmail sending addresses: An alias appears under Settings → Sending addresses and in the composer's From menu when the alias and its domain are active and sending is enabled. You can set its display name, Reply-To address, signature, and default status there.

If the alias delivers to a connected Gmail, Outlook, or other inbox, you can link it to that inbox as an extra From address. If mail arrives elsewhere, use Add a From address instead. A receive-only, disabled, deleted, or unavailable alias cannot be used for sending.

An alias on a domain whose incoming mail stays with another provider is not added automatically. Add it once with Add a From address so it sends with that domain's settings. See Send From a Domain You Do Not Host.

What happens when you downgrade

Downgrading between alias-capable plans does not delete existing alias records. If the mailbox is above the new plan's limit, you cannot create another alias until usage is back within the limit.

Nano does not include the alias entitlement. It can retain up to five saved aliases, but they remain inactive and webmail does not expose them for sending. If aliases are operationally important, move the addresses before downgrading or re-upgrade to an alias-capable plan.

API and MCP access

Aliases are fully manageable via the REST API and MCP tools:

• API: GET/POST/PATCH/DELETE /api/v1/mailboxes/{id}/aliases, create, list, update, and delete aliases programmatically. The GET /api/v1/account endpoint includes max_aliases_per_mailbox in the limits section.
• MCP: Four tools, list_aliases, create_alias, update_alias, delete_alias, for managing aliases through AI agents like Claude, ChatGPT, or automation platforms.
• Search: Both web and API search include alias addresses. Searching for "info@" will find the mailbox that has info@domain.com as an alias.