there is not a way to run a CC to hold for a tab, but you could store it as a card on file to pull it back up later. https://squareup.com/help/us/en/article/5770-use-card-on-file-with-the-square-point-of-sale-app
We are also looking to start tabs with a CC and return the card to the guest. As of now we are holding on to the card until they are ready to check out. It would be so much easier for everyone invloved if we could hand back the card and it saves the info to run later for a one time use purpose. Putting a card on file would invlove asking the customer for their permission to save their info. I have a feeling customers will not want us to save their info so they can order a beer or two. Please help as I have seen other POS's work this way!