If I got married in 2020, do I need to do a 2019 tax return for the spouse so it is included for comparison in 2020?
If you are asking about Filing a tax return for your spouse (i.e., your spouse did not file a 2019 return...) , you should ALWAYS stay caught up on filing requirements as now you are one entity, Spouse 1 and Spouse 2 (I am trying to stay PC here...). If you are talking about getting your spouse's 2019 data onto the system for comparison purposes, I guess you could prepare a "dummy" Married Filing Joint Return for 2019 with yours and your spouse's data combined. Remember, in 2019, if both of you were unmarried, you would have filed "Single" returns so if you do not do it this way (combine and prepare it as Married-Joint) you will be comparing apples to oranges. If your spouse filed a 2019 return, DO NOT FILE ANOTHER 2019 RETURN ! Make sure this "dummy" 2019 return is labeled appropriately with both of your incomes (filing married-joint) if the comparison information is important to you.
No, you don't do a Married Filing Jointly 2019 income tax return since you weren't married in 2019. For tax year 2020, the year over year comparison won't be accurate.
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