Solved
I received a K-1 from 2015 that I didn't submit last year. I'll also be receiving one for 2016. Can I submit them both with my 2016 taxes?
No, IRS only allows the income for a particular year to be included on that year's return. In order to add the 2015 K-1, you'll need to amend the 2015 return by filing a 1040X. You can do this in TurboTax.
IRS accepts the 1040X (amended return) on paper only, so after preparing it you'll print, sign, and mail it.
Here's the link to the TurboTax support page for amending returns, which will get you started: https://turbotax.intuit.com/tax-tools/tax-tips/IRS-Tax-Return/Amending-Your-Income-Tax-Return/INF12058.html
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