How to create and add subscribers to a new list

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 only 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
     
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")
       
     • 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”].

Create a new list

1. Navigate to the Lists & Segments tab
2. Click Create List/Segment in the upper right corner
3. Choose List
4. Give your list a name and add any applicable tags
5. Click Create List
6. Set any flows 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 Contacts

9. Select your CSV file by uploading from your computer or dragging and dropping it into the upload box

10. In the Email row, click Subscribe to Email Marketing (only if everyone in your CSV file has provided explicit consent to receive email from your brand) 
    • Learn more about email consent
11. Map the columns in your uploaded CSV to Klaviyo fields, which represent where your data is stored on your contacts in Klaviyo
    • 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 and select the data type
        OR
      • Add a new custom property by typing the new property name and selecting Create option
        
12. If your CSV includes email addresses or phone numbers for subscribers who have explicitly opted in, click Subscribe to Email Marketing or Subscribe to SMS Marketing, as appropriate
    • Warning: only subscribe contacts to a marketing channel if they have provided explicit consent to receive marketing via that channel from your brand. 
13. Review your import to make sure you are ready to proceed
14. Click Import Review
15. Click Start 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

• Troubleshooting list imports
• Why having a single main list is beneficial
• How to upload and segment with consent