Printful is completely white-label, meaning there is NO Printful branding anywhere on or inside a shipment's packaging.
You can choose to upload your own custom branding sticker which will be printed on the shipping label and placed on the outside of your packages! Upload your branded logo by going to the dropdown menu that reads, "signed in as..." From there, you'll select Stores. Once you're in stores, select Edit. Here you can also include your own customized message on your packing slips! If you have uploaded a custom branding sticker for your store, that same image will be used on your packing slips as well.