Hi there, @bobwisecarver,
Thank you for reaching out to us about this! Since a tip is considered a line item, you can refund it individually. Issuing a refund for a tip will not allow you to adjust the amount since you are unable to issue a partial refund on an item. In order to receive a tip after it's been refunded, you will need to reprocess your customer's card.
Ellie
Community Moderator, Square
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