When it comes to uploading your custom reviews from a CSV file, the first step you will need to do is to go to the "Import reviews" and download the "CSV template":
Then, you will need to fill that file with your reviews. You can just copy-paste them inside the CSV file.
Once you have your reviews in the CSV template, go back to the import page and click 'Upload file,' make sure the Date format is the same as in your template, for example, YYYY-MM-DD, and click the top right 'Upload reviews' button:
And that's it! Your uploaded reviews will appear in the selected source
The Reviews Import tool accepts data in comma-separated values (CSV) file format. You can upload a maximum of 500 reviews in one file, but we recommend 90 reviews to be uploaded at once.