Mail Admin (Client Portal)For: Organisation administrators2 min readUpdated 2026-10-10

CSV import file format reference

Exact columns, limits and rules for the user import file.

Use a header row

The first line must be email,name,quota_mb,password,send_to. Quote values that contain commas, for example "O'Neil, Pat".

Up to 200 rows per import. The whole file is checked against your mailbox limit before anything is created, and rows with problems are skipped.

Rule	Detail
Required column	email
Maximum rows	200 per import
Password empty	A strong password is generated and shown once
Welcome e-mail	Sent to send_to when you tick the option
Duplicates	Existing addresses are skipped with “Already exists”

Create up to 200 mailboxes at once, check the file first, and download the one-time passwords.

Add a new mailbox and send the person their login details.

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