How to create and add contacts to a new list

Last updated at:

You will learn

Learn how to create a new list in Klaviyo and how to add contacts to it by uploading a CSV containing their contact information.

Why use lists

Lists can be used to send campaigns, trigger flows, and keep track of how your audience is growing over time.

It's important to add contacts to a new list when pulling them from another email service provider and getting started with Klaviyo as well as when you collect a list of contacts from an event, giveaway, or signup form. You can have up to 1000 lists and segments in your account at any given time. 

Before uploading a list

Before uploading your list make sure to answer the following two questions:

  • Does my list abide by Klaviyo's Terms of Service?
  • Does my list include opted-in subscribers who subscribed by filling out a signup form or providing their email address at an event you attended?

If you're unsure or answered no to either of the questions above, then review our guidelines for compliant lists before uploading your list.

Requirements for formatting CSVs

There are some important requirements for formatting your data: 

  1. Your list of contacts should be in CSV format
    • If you're working in Excel or another spreadsheet program, save your data to a CSV file by clicking File > Save As and selecting CSV as the file format
  2. The maximum allowed file size is 50 MB
  3. The header of the first column in your CSV should be one of the following:  
    • Email
    • Email Address
    • Phone Number
      A Google Sheet containing a list of contacts formatted for upload into Klaviyo
  4. The order of the other columns doesn't matter and can be used to add information to Klaviyo or custom properties
    • Klaviyo properties
      • Use the Klaviyo property name as the header for the column so that the data in that column is automatically mapped to the corresponding Klaviyo property and the data type is automatically selected
    • Custom properties
      • Name each column with the intended custom property name; for example, if you are importing birthdays, name the column "Birthday" and give each row a value (e.g., "1992-06-21")
        In a CSV file, a date column is highlighted, formatted as YYYY-MM-DD
      • Dates
        • Insert dates in an accepted format (YYYY-mm-dd) (HH:MM:SS); dates must be imported in an accepted format in order for Klaviyo to recognize the value as a date

Keep the following in mind when uploading contacts via a CSV

  • Any new value/column that you include in a CSV upload that does not already exist on a contact's profile will:
    • Be added as a new custom property
    • Not affect existing custom properties
  • Any value/column that you include in a CSV upload that already exists on a contact's profile will be overwritten in the most recent upload
  • 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”].

In a CSV file, a custom profile property in list format is highlighted

Create a new list

  1. Navigate to the Lists & Segments tab
  2. Click Create List/Segment in the upper right corner
  3. Choose to create a new List
  4. Give your list a name and add any applicable tags
  5. Click Create List
  6. Set any flow triggered by this list to Manual; otherwise when you upload contacts, everyone in the file will be queued for the first email in the series, even if they subscribed to the list months ago
  7. Check the formatting of your CSV
  8. Click into your list and select Upload ContactsIn Klaviyo’s list creation tool, a cursor hovers over Upload Contact


  9. Select your CSV file by one of the following:

    • Uploading from your computer or dragging and dropping it into the upload box

    • Uploading via copy/paste
    • Using the Quick Add option (this is only recommended if you're adding a couple people to a list

  10. Map the columns in your uploaded CSV to Klaviyo fields, which represent where your data is stored on your contacts in Klaviyo
    • If you don't have GDPR consent fields already stored in your CSV:
      1. Click Add GDPR specific consent
      2. Specify the types of consent the contacts on your list have given; this information will be stored on their profile as custom properties
    • If you're uploading Klaviyo properties, the data type is already selected for you and you're unable to modify it
    • If you're uploading custom properties:
      • Select the field you'd like to map them to
      • Select the data type
      • Add a new custom property by typing the new property name and selecting Create option
        In the import review stage, a custom profile property is unmapped. The user has typed in a new property name and their cursor hovers over the Create option selection.
  11. Review your import to make sure you are ready to proceed
  12. Click Import Review
  13. Click Start Import

In the final stage of importing a list to Klaviyo, green checkmarks indicate that the list is ready to import.

When your import is successful, you will see a success message appear confirming this.

If the information was not imported correctly, you will likewise be alerted with information around what data was skipped. 

Additional resources

Was this article helpful?
797 out of 1346 found this helpful