I am a US citizen living full time in Mexico, married to a Mexican national. I pay US taxes on a small amount of income that I earn through US sources. Filing taxes as a married person requires me to get an ITIN for her (I am filing separately) She has no income from US sources but does work. Does she have a US tax liability through me? Does she have to file too if she has an ITIN?

Thanks for any assistance, I really appreciate it.

You can file resident tax return as Married Filing Jointly. You will get standard deduction of $10,700 and exemptions for both of you and the kids.

You will complete forms W7 (application for ITIN) for your spouse and children and attach with your tax return.

You can also file as Married Filing separately and get exemption for your spouse if she did not have any income. Still you will attach W7.