Hi,
if I am a Mexican resident citizen, SMLLC owner, and qualify for full tax exemption under U.S./Mexico Treaty, do I still have to file form 1040NR or are there other forms? Does sch C still apply?

Thank you

#1;UNLESS you are a US resident for tax purposes, then you need to file form 1040NR. You need to file Form 1040NR aslongas you were a nonresident alien engaged in a trade or business in the US.

#2;You need to report your US source income, self employment income from US NOT from Mexico UNLESS you are a US resident for tax purposes ,on Sch C of 1040.

If you operated a business or practiced your profession as a sole proprietor,an owner of SMLLC, you need to report your effectively connected income and expenses on Sche C of 1040. If you are a self-employed nonresident alien living/doing biz in the US you must pay SE tax if an international social security agreement in effect determines that you are covered under the U.S. social security system. If your self-employment income is subject to SE tax, you need to complete Sch SE and file it with your Form 1040NR. If not due to tax treaty between US and Mexico , then you do not need to file Sch SE of 1040.