Hello, tax folks. I would appreciate your input on this situation:

• unsure about whether filing is required and how much tax owed
• already filed extension, with 0 for expected tax and payment
• now considering making an extension payment "just in case" there is tax due and to avoid penalties/interest

If I make this payment and it turns out I actually don't have a filing requirement, would I still have to file a 2021 return to get the payment back?

Is there some way I could instead claim it in next year's return without filing a 2021 return, or get it recharacterized/transferred into another format like estimated tax payment for 2022, etc?

(Side question: Since I already submitted an extension form with 0 for payment, can I even submit a payment now or would it confuse the system?)

Looking to avoid both penalties and unnecessary paperwork...

Thank you!