J-1 research scholar tax exempt

[clariidaewhite]

I held J-1 research scholar as a Post-doc position. I came to the US in Jan 2024 and i would like to apply a tax exempt (from Thailand). My ds2019 period is jan 2024- jan 2025
i worried about if i extend my visa more than 2 years, should i payback the tax?

For example, J-1 visa (2024-2025 and continue 2025-2026) with tax exemption ->if i continue j-1 again from 2026-2027 (start to pay tax), should i pay back tax that i exempt (with penalty or any issue)? Now i’m planning to stay less than 2 years but i don’t know that future plans can be changed. 

thank you

[DaveF1006]

As long as you are in the exempt period, you do not pay any FICA taxes.  Once your exemption period ends after 2026, you will become a RA and will start paying FICA taxes. You are not responsible for paying FICA taxes back that were not paid during the time you are exempt.

[clariidaewhite]

Thank you for your answer. it is really helpful.

After your suggestion, I tried to apply tax treaty but i got an Alert that "This treaty contains time-based retroactive loss provision/s. Exceeding the stay over the treaty maximum time limit will cost loss of benefits retroactive back to the first dollar earned." and in the exemption documents (From 8233) also have shown the message that "The treaty exemption is available only for compensation paid during a period of two years beginning on that date. The entire treaty exemption is lost retroactively if my stay in the US exceeds two years."

This is in case that I have to pay back if I stay over 2-year?

If I have to pay back all 2 years that I was exempted, How to pay back (with or without benefits)

Is it contain any penalties? 

[DaveF1006]

To clarify, as soon as your initial exemption period was over, did you start filing as a resident alien or did you continue to file 1040 NR?

@clariidaewhite