I e-filed my 2018 return through TurboTax and owed $2500. I have not made a payment, and planned to pay by check in April. In the meantime, I realized that I used an incorrect cost basis and overstated my income. My amended return shows a $216 refund. Do I need to wait to file the amendment until I pay my taxes? Can I file the amendment now and only pay the net amount due?
Amendments take a long time to process. Up to 16 weeks. It is best to pay the original amount by the due date of the return. Then once the original is fully processed, file your amendment. This will avoid errors in IRS processing.