Import contacts from a CSV file

Smartletter reads a CSV file up to 5 MB and 50,000 rows. You can import up to 10 files per hour.

The file needs an email column. Name, first name, last name and language are optional. Headers can be in any order.

Commas or semicolons both work as separators (French Excel uses ;). Quoted cells and line breaks inside cells are fine.

email,first_name,last_name,language
anna@example.org,Anna,Martin,en
leo@example.org,Leo,,fr

No header row? Smartletter takes the first cell that looks like an address in each row.

Pick an Export format, or keep Detect automatically. Smartletter recognizes exports from:

• beehiiv
• Substack
• Mailchimp
• Kit (ConvertKit)
• Ghost
• Other (email column)

These exports carry open and click history. Smartletter imports it, so your most active readers get your emails first.

Contacts marked as unsubscribed, bounced or cleaned on the old platform are left out.

Have custom fields? The Columns to custom fields step links each column to a field. Columns named like a field's key or label are matched for you. A cell that does not fit the field's type is left empty and counted.

1. Go to Import contacts.
2. Choose the Destination segment: the newsletter these contacts join.
3. Choose your CSV file and the export format.
4. Link extra columns to your custom fields, if you have some.
5. Tick the box: every contact agreed to get your emails, and you don't use bought, rented or scraped lists. The import won't start without it.
6. Click Import.

Owners, admins and editors can import. Viewers cannot.

Before saving anything, Smartletter checks every address. It leaves out:

• Invalid address: the format is wrong.
• Unsubscribed on the previous platform: the export says they left.
• Typo in the domain: for example gmial.com or orange.fe. The report suggests the right address.
• Placeholder domain or spam trap: domains like example.com or test.com that no real person uses.
• Role address: shared boxes like contact@, info@ or support@. Nobody personally agreed to your emails there. hello@ and team@ are kept.
• Disposable address: throwaway inboxes that expire.
• Domain without a mail server: the domain has no MX record (the record that says a domain can receive mail).
• Duplicate or already present: the address is twice in the file, or already in this newsletter.
• On the suppression list: the person unsubscribed, or the address bounced or complained. See Unsubscribes and suppressions.
• Over the plan limit: the Free plan stores up to 500 subscribers per newsletter.

After the import, you see how many rows were read, imported and left out, with the count for each reason.

Likely typos are listed with their fix. Correct your file and import those rows again.

Click Download the report (CSV) to get each left-out row: line, email, reason and suggestion. The file details up to 20,000 rows. The totals stay exact.

Your past imports and their status appear under Recent imports.

Imported contacts start as Pending. They get nothing yet. Smartletter checks each address with DeBounce, an email checking service. This takes a few minutes.

• Addresses that don't exist are removed from your list.
• More than 5% bad addresses: the import goes to manual review.
• More than 15% bad addresses: the whole import is refused.
• Otherwise the contacts become Active and can get your emails.

On the Free plan, a random sample of 500 addresses is checked, not the whole file.

Some imports are always reviewed by hand, within 24 hours: when your workspace is less than 30 days old, when the file has more than 1,000 valid addresses, or when the list looks risky (many throwaway, shared or dead addresses). The contacts stay pending until then.