It is almost always better to file jointly but you can try it both ways and compare.
you would have to do the return both ways to see what the result is, but i can state this: 96% of married couples file joint! and that is because the tax laws motivate that behavior. I suspect within that 96% are many, many married couples where one ones a business and one is W2.
the other 4% - probably situations where two people are not getting along and a very few where it does make financial sense.
And you are filing a separate Business 1120 S corp return for it? You will get a K-1 or W2 from the S corp to enter into your personal tax return.
In almost all cases Married Filing Joint is best. The S-Corp will have to file a return for that business but
The S-Corp will have to file a return for that business but your S-Corp income will flow through to your individual tax and TurboTax can handle this without any problems.
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