How to import subscribers to a list

You will learn

Learn how to add subscribers to a list in Klaviyo. Uploading contacts is key when getting started with Klaviyo, particularly if you’re migrating from another service provider or pulling in information from a third party.

Before you begin

Please note the following before starting the import process:

• Your list must abide by Klaviyo's Terms of Service.
• Turn off any flows triggered by the list you’re uploading, unless you want the flow to send to all of the imported contacts.
• Uploads do not trigger double opt-in
• Your CSV file must be 50 MB or less. Larger uploads must be split into multiple CSV files.

Upload a CSV to a list

Format your CSV

Place email addresses or phone numbers in the first column

In general, the first column should be your customers’ email addresses (labeled either “Email” or “Email Address”) or phone numbers (labeled “Phone Number”). If you are importing SMS subscribers, we recommend reading through our guide on uploading SMS consent.

Optional: indicate consent status

If your list contains a mix of subscribed, unsubscribed, and never-subscribed contacts, include a column for each type of consent you want to import, such as:

• Email Marketing Consent
• SMS Marketing Consent
• SMS Transactional Consent

Use one of these values in each consent column:

• Subscribed
  Person is opted in to receive messages.
• Unsubscribed
  Person used to be subscribed but has since opted out. You cannot send messages if they are unsubscribed for that channel (e.g., you cannot send an SMS to someone who’s unsubscribed from text messaging, but you may be able to send an email, and vice versa).
• Never subscribed
  Person never consented to receiving messages for that channel. Importing “Never subscribed” leaves existing consent unchanged. A blank consent cell also leaves it unchanged unless you supply a consent timestamp. You cannot send SMS without the appropriate SMS consent. Never-subscribed email contacts can still receive emails and count as active profiles if they are not suppressed.

To record when someone gave consent, add a separate timestamp column, such as Email Marketing Consent Timestamp, containing the consent date in an accepted date/time format. A valid timestamp with no consent status subscribes the contact for that consent type.

For consent types not covered by your file, you may be asked whether to apply bulk consent. Apply it only when every contact with an identifier for the selected channel (such as an email address or phone number) has given that consent.

If you are importing a list to resubscribe profiles, do not include backdated consent timestamps in your CSV as they may be skipped during import.

Optional: add other properties

Your CSV can include additional columns if you want to upload more properties for that profile. These properties could be anything, from their name, birthday, date they subscribed, last click, etc.

• If using a Klaviyo property, use the Klaviyo property name as the header for the column.
  • This allows that column to be easily mapped to the right property with the correct data type.
• Dates must be in an accepted format (e.g., YYYY-mm-dd HH:MM:SS).

Please also note that when adding properties:

• Any new value/column that you include in a CSV upload that does not already exist on a contact's profile will:
  • Create a new custom property
  • Not affect existing custom properties
• If the value already exists for a profile, the value from the CSV will overwrite the prior value.
• If you're interested in uploading a list of values for a single property (such as “Sizes”), you will need to use JSON syntax. Create an array of your values that looks like this: ["value1", "value2", "value 3"].

Import contacts with consent

1. Navigate to Audience > Lists & segments.
2. Select the list you want to add your contacts to (e.g., Newsletter).
   • If you want to create a new list, select Create > List, enter a name, and click Create list.

3. Open the Manage list dropdown in the upper right.
4. Choose Import contacts from the dropdown.
   • If the option to import contacts is unavailable, check that you have the correct user permissions to upload contacts and that you are viewing a list, not a segment.
     

5. Click Upload and select your CSV file of contacts.
6. Map each column you want to import to an appropriate property in Klaviyo. Check the data type and deselect any columns you do not want to import.
7. If your mapped consent columns cover all available consent types for the channels in your file, the button is Import. Otherwise, click Next to review the bulk-consent choices.
8. If the bulk-consent screen appears, review which consent types will use values from your file, then choose whether to add consent for any remaining types:
   • Select Apply bulk consent only if the contacts have given the consent you want to add.

• Choose the channel and, where shown, the message type to apply, such as Email or Text Message > Marketing messages.

• To use only the consent recorded in your file, select Only import the consent in my file. Existing consent stays unchanged for any consent type your file does not update.

9. When ready to proceed, click Import.

The import process can take up to a couple of hours to complete. Please wait a few additional hours before you turn your list-triggered flows back on (if applicable).

Review the import status and number of imported contacts on the import history page. If records were skipped, review the errors and follow the troubleshooting list imports guide before uploading a corrected file.

Once the CSV finishes importing, Klaviyo will either create a new profile or associate the data to an existing profile.

With email for instance, Klaviyo looks for any existing profiles with that same email. Then, Klaviyo updates the properties you chose to import and applies the consent specified in your file or bulk-consent choices.

Upload via copy/paste

As an alternative to uploading a CSV file, you can copy and paste a list of subscribers to upload them.

1. Navigate to Audience > Lists & segments.
2. Select the list that you want to add subscribers to.
3. Click the Manage list dropdown in the upper right-hand corner.
4. Click Import contacts.
   1. If the option to import contacts is unavailable, check that you have the correct user permissions to upload contacts and that you are viewing a list, not a segment.
5. Click Switch to copy and paste CSV beneath the bottom-left corner of the upload tool.
   

6. Paste contact information in this format:
   Email,First Name,Last Name
   someone1@example.com,George,Washington
   someone2@example.com,Abraham,Lincoln
   

1. Click Next.
2. Map each column you want to import to an appropriate property in Klaviyo. Check the data type and deselect any columns you do not want to import. If Next appears, click it to review consent. If Import appears, the mapped columns already cover the available consent types.
3. If the bulk-consent screen appears, choose whether to apply consent beyond what is in your pasted data:
   • Select Apply bulk consent only if every contact with an identifier for the selected channel has given that consent.

• Choose the channel and, where shown, the message type to apply, such as Email.

• To use only the consent in your pasted data, select Only import the consent in my file.

4. Click Import.

Add individual subscribers (email only)

If you would like to quickly add a handful of individuals to your list, you can use Add profile instead.

1. Navigate to the list you'd like to add the profile to.
2. Click Add profile.
   1. If the Add profile button does not appear, that means you either do not have the correct user permissions to upload contacts, or this is a segment, not a list.
      

3. In the drawer, fill in the Email field.
4. If the person has explicitly opted in to receive emails from you, check the box for Profile has granted explicit consent to receive email marketing.
   

5. Optional: add other information about the contact, such as their name or title.
6. Click Add subscriber if you selected the consent checkbox, or Add profile if you left it unchecked.

Bulk remove consent

If you want to remove consent for profiles, you can use essentially the same import process.

The only differences are that you must:

• Have a column for the type of consent (e.g., Email Marketing Consent).
• Add “Unsubscribed” for each profile within that column.
  • Note that you cannot reset profiles in bulk to “Never Subscribed.”

If the bulk-consent screen appears, select Only import the consent in my file, then click Import. This applies the unsubscribe statuses without adding consent for other channels or message types.

Additional resources