In the LTV Numbers side navigation bar, click "Upload" to get to the Data Uploader
Click the "Choose File" button
Select your file and click Next
Note: if you have multiple files of the same format, you can multiselect them to upload them all at once. Ensure each file is the same data type. Do not select files for payments and contacts for different platforms all at once.
Select the data type that matches your file in the Data Format selector, then click Next
Note: for advanced users with non-standard data formats, follow these instructions on Creating A Custom Data Format. Or select it in the Data Format selector if you've already created one.
Ensure you selected the correct data format, then click Upload to begin the upload process for your file
Note: this process may take some time to complete
Optional: Repeat this process for any additional data types you need to upload