Manish

Hello, I am a U.S. resident with Indian passport. I moved from U.S. to London in 2019 for a period of 3 years on a secondment (it was an internal company transfer) before coming back to U.S. in 2022. My question is, can I get my National Insurance (NIC) deduction back or associated with my social security in U.S. I read few sources where it says that it should happen as there is a treaty between U.S. and UK but I am not quite sure what’s the process. What are my options here? Please advise, thanks!