It looks to me like Postmates is one of those outfits where both of you will be considered "independent contractors" (self-employed) and if either of you earned more than $600 you should receive a 1099-MISC with the income in Box 7. Irrespective of whether you receive a 1099-MISC or not you are obligated to report your income on your income tax return. If you don't get 099-MISCs you calculate your revenue based on your own records.
You report your income on Schedule C, (one for each of you), and on Schedule C you'll deduct any associated costs connected with earning that income. Your taxable income from self-employment will be taxed at ordinary income tax rates. You will also be assessed a Self-Employment tax (Social Security and Medicare) that calculated at a roughly 15% tax rate. TurboTax will do all the calculations for you based upon your Schedule C input.
In order to complete a full Schedule C with revenue and expenses using an online product you will need to upgrade to TurboTax Self-Employed.
Tom Young
Enter your E-mail address. We'll send you an e-mail with instructions to reset your password.