You won't find the Oregon Tri-Met tax form on any local tax "drop-down" list in TurboTax; but you will find it in the Oregon state TurboTax module. It's really easy to access, once you know how, although at the same time it can be relatively easy to miss when going through the interview. Here's how to find it, and begin to fill out, the Tri-Met tax (Oregon Form TM).
First, simply start the Oregon state TurboTax module interview, and have entered some self-employment income activity on the federal side of the TurboTax program.
Second, proceed through the Oregon module interview (or revisit it if you've already gone through it once), and continue until you reach the "Other Forms" sub-group.
Third, from there, you'll simply indicate that you need a Form TM added to your state of Oregon tax return; and then follow the rest of the Oregon program interview. (As a side note, please don't forget the Multnomah County / City of Portland Business Tax, as well as the Portland Arts Tax, if they are applicable to you . . . as all three tax forms are generated from this same place in the Oregon program, as well as the Lane County transit tax form.)
Please see also the attached screen-capture images below as a visual reference guide; simply click them to open.
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