Bulk Mailbox Creation

Create up to 500 mailboxes at once by uploading a CSV file or pasting tabular data. You provide the email addresses and passwords; mailboxes are created immediately.

Who this is for

• Admins provisioning many accounts at once (e.g., new team, new department, new domain).
• Users migrating from another provider who already have a list of addresses and passwords.
• Anyone who needs admin-controlled credentials for multiple mailboxes.

Tip: If you want recipients to choose their own passwords, use Bulk Invites instead.

Before you start

• Active domain: Add your domain(s) first. Mailboxes can be created on pending domains, but emails won't flow until DNS is verified.
• Plan limits: Each domain has a mailbox limit based on your plan (Nano: 10, Starter: 100, Pro: 300, Agency: 1000).
• Password requirements: Every password must be at least 12 characters and include uppercase, lowercase, and a number.

Step 1: Prepare your data

CSV format

Example CSV

email,password
john@example.com,SecurePass123
jane@example.com,AnotherPass456,5 GB
support@example.com,HelpDesk789!,2048 MB

The optional storage column controls how much storage that mailbox gets:

• Empty / column missing — uses the shared pool (the default). All shared mailboxes draw from the same account allowance.
• 5 GB, 2048 MB, 1.5 GB — pre-allocates that exact amount; the mailbox cannot exceed it. The total of all dedicated allocations across the batch must fit in your remaining account pool, otherwise the batch is rejected with a clear message.

You can mix shared and dedicated rows freely in the same upload.

Supported formats

• Comma-separated (CSV) -- standard .csv files
• Tab-separated -- paste directly from Excel or Google Sheets
• With or without header row -- auto-detected if the first row contains column names like email, password

Step 2: Enter your data

1. Navigate to Mailboxes in the left sidebar.
2. In the Create New Mailbox card, select Bulk create.
3. Paste your data into the text area (one account per line), or drag and drop a .csv file (up to 10MB) into the upload area below.
4. Click Validate.

Step 3: Review preview

A compact domain limits table shows how many mailboxes you can still create on each domain (used / limit / available).

Below it, all rows are listed in a single table with columns: Email, Password, Status, and Action. Rows with issues appear first so you can fix them before scrolling to the ready ones.

Fixing weak passwords

• Generate -- creates a strong password instantly. The row moves to Ready and the new password is shown so you can copy it.
• Edit -- click the pencil icon next to the password, type your own, and press the checkmark. Password must be at least 12 characters with uppercase, lowercase, and a number.

Removing rows

Click x on any row to remove it. If you remove a Ready row, the first Over Limit row for the same domain is automatically promoted to Ready.

Step 4: Create mailboxes

When satisfied with the preview, click Create X mailboxes. Each mailbox is created individually -- if one fails, the rest still succeed (partial success).

After creation:

• Download Credentials: Click Download CSV to save a file containing all created email addresses and their passwords. Share this file securely with mailbox owners.
• DNS warnings: If any domains aren't DNS-verified yet, a warning shows which ones need attention.
• Failed rows: Listed with specific error reasons so you can fix and retry.

Important: The credentials CSV is generated once and not stored on the server. Save it immediately.

Limits

Troubleshooting

API access

You can also bulk create mailboxes via the REST API:

POST /api/v1/mailboxes:bulk

See the API Overview for details.