Thank you for reaching out to the Community. Great question, the 1099-K form from Shopify reports transactions processed through Shopify Payments only. In this case, other payment processors such as PayPal, would be responsible for producing 1099-K for transactions they handled. For more information on this, you can refer to our Tax Reporting documentation as it touches on this further.
As for what the 1099-K form reports on, it includes gross transaction value. It does not factor in refunds, chargebacks, credit card processing fees, adjustments or any bills paid with using Shopify Balance.
Please let me know if you have any other questions!
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