How to add your subscribers
There are three ways to bring people into your list, and one of them is not available on every account.
Who sees the Import CSV button
File import is available on any paid plan, self-service or agency. It is not available on the Free plan at all: a free account is created in seconds, with no verification, and a bought or unreliable list brought in through one would put the sending reputation of every client on the platform at risk, not just that one account.
- Add subscribers one at a time, from the Subscribers page, with name, email, and tags
- Publish a subscribe form on your site, so people join the list themselves
The second option is also the one that builds your consent record without any extra work. How to put a form on your site is in "Sign-up forms: bringing people in without adding them yourself".
Importing from a CSV file
The button sits on the Subscribers page, between Export CSV and Add subscriber.
File structure
- email: required
- name: optional
- tags: optional, several tags separated by commas
- metadata: optional, in JSON format
- consent_given_at: the real signup date, in YYYY-MM-DD format
The file must be UTF-8 and under 5 MB. You can run at most 10 imports per hour.
The column you cannot fix afterwards
consent_given_at is the only column a second import cannot correct. Without it, every subscriber appears to have signed up on the day of the import, which is exactly the proof you are missing when someone asks where you got their address.
Mailchimp and Brevo exports contain the date, but after a list consolidation it usually ends up buried in the metadata JSON, where the import does not look. Lift it into its own column before you upload.
The legal basis is chosen once, for the whole file
The dialog asks on what basis you have the right to email these people, with four options: "They signed up themselves, with their consent", "They are clients or collaborators of mine", "I have a contract with them", or "Legitimate interest, which I can justify".
The choice applies to the entire file. An inherited list almost always has different bases in the same file: people who signed up on the site, and people added because they are press. Split the list first, one file per basis, and import them separately.
Do you also send the welcome email to this file?
Below the legal basis there is a checkbox: "Send the welcome email to the people in this file". It is off by default on every import, even if you checked it last time. Checked, it enrolls everyone the file brings in into the flows whose trigger is "When a new subscriber joins", exactly as if they had just signed up through a form.
Only check it if the people in this file actually expect to hear from you right now. An old list or an archive gets a "welcome" it no longer recognizes, exactly the kind of email that produces spam complaints. Left unchecked, the welcome flow does not start at all for imported people: it only starts automatically for someone who signs up through a form.
What happens during the import
The result shows how many subscribers were imported and how many processed. Skipped rows appear separately with the reason, and rows with errors show the exact message. An email already in the list is marked as a duplicate and skipped. It is not overwritten and does not create a second entry.
If the file goes over the room left on your plan, the contacts that do not fit are not imported at all, and existing contacts are left untouched. Upgrade or free up room, then re-import the same file: the ones already added are skipped as duplicates, not added a second time.
A subscriber skipped as a duplicate does not receive the new tag from the second file either. If you import the same people again to add one more tag, the tag is lost silently. Import once, with the tags in place from the start.
Test on two addresses before the big file
The Subscribed column in the list shows today's date for everyone, because it displays when the row was created in the platform, not when the person gave consent. Consent is only visible in Export CSV, in the consent_date column.
Import two test addresses first, with old and distinct opt-in dates. If the export shows them exactly, the big file can go in.
Articles in the same category
- Tags and dynamic segments
How to apply tags, what the segment builder can do, why the starter templates do not work after an import, and how tags behave when you send.
- Sign-up forms: bringing people in without adding them yourself
A form hosted by us, with a direct link or a code to paste on any site. What fields it can collect, which tags start the right flows at signup, and the difference between GDPR on the form and the account-wide email confirmation.