If your wife has a certain kind of business, the business needs a separate return prepared first. Businesses that require separate business returns are LLCs with more than one owner, S-corporations, C-corporations, and unincorporated partnerships with more than one owner who are not spouses. This kind of business or partnership tax return requires a separate program called Turbotax Business, which is a CD or download for PC only (no online or Mac version) and is due March 15, not April 15.
For any other business, your wife would file a schedule C attached to her personal return that lists business income and expenses, that flows to the main form 1040.
Then, married couples always have the option of filing a joint return. This is a single return that lists the income and deductions of both spouses to get one joint combined tax bill and joint combined refund. You can file jolty even if one spouse has much higher or lower than the other spouse and even if one spouse is self-employed and the other is not. Joint filing has lower tax rates and better deductions.
If you don't agree to file jointly or can't for some reason, you have the option to file as married filing separately. Each spouse prepares a return listing their individual deductions and income. Separate filing usually results in a higher tax bill since many deductions and credits are reduced or disallowed with joint filing.
If using Turbotax installed on your own computer from a CD or download, you can prepare more than one tax return. Just give each file a different name, each tax return is a separate document like having multiple word processor or spreadsheet documents. If using turbotax online and you want to file two separate returns, you need to create two separate accounts with different user names and passwords (they can share an email address).
