We are a married couple from Europe living in the UK. I work on an 01 visa full time in New York, my partner does not work and is on the 03 visa. We have been in the USA for one year and a half. Can we file jointly? If my partner does not have a SSN, as they cannot work on their visa?
Do we qualify to pass the substantial presence test, and can file jointly as residents?

We are a married couple from Europe living in the UK. I work on an 01 visa full time in New York, my partner does not work and is on the 03 visa. We have been in the USA for one year and a half. Can we file jointly?=====>I guess you need to check your visa status . I mean aslongas you are treated as a US resident for TAX PURPOSES by the IRS NOT BY THE INS, then, yes you can file your return jointly as MFJ with your spouse with O3 visa. If not then no. Since you hold o1 visa, and were in the U.S. for at least 183 days in the prior year, you are considered a resident taxpayer. Then, you may file your US return as MFJ.

If my partner does not have a SSN, as they cannot work on their visa?=====>He needs a ITIN instead of a SSN#;IRS issues ITINs to foreign nationals and others who have federal tax reporting or filing requirements and do not qualify for SSNs. You rspouse, an O3 visa holder, as a non-resident alien, is not eligible for a SSN# required to file a U.S. tax return only to claim a refund of tax under the provisions of a U.S. tax treaty, needs an ITIN.He needs to file from w7 for his ITIN. An ITIN does not authorize work in the U.S. or provide eligibility for Social Security benefits or the Earned Income Tax Credit.

Do we qualify to pass the substantial presence test, and can file jointly as residents?=======>To file your US return as MFJ, you must pass the SPT; Since you hold o1 visa, and were in the U.S. for at least 183 days in the prior yearof 2014, you are considered a resident taxpayer. For more info plz contact the IRS