According to IRS Pub. 560 - Retirement Plans for Small Business:
Sole proprietors deduct contributions for themselves on Schedule 1, line 15 of Form 1040.
To do this in TurboTax Home & Business, please follow these steps:
- On the Business Income & Expenses screen, scroll down to the Less Common Business Situations section and click on the Start/Update box next to Self-Employed Retirement Plans.
- On the Self-Employed Retirement screen, click Yes.
- Click Yes on the next screen, also titled Self-Employed Retirement Plans.
- Enter the contribution on the screen, Individual and Roth 401(k) Plans, in the elective deferrals box.
In TurboTax Self-Employed (online)
- Click on Wages & Income and scroll down to Other Business Situations.
- Click the Start/Revisit box next to Self-Employed Retirement Plans.
- On the screen, Self-Employed Retirement Plans click the Yes box.
- Enter your contribution on the next screen.
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Contributions you make for your employees are deducted on Schedule C.
You can enter them as employee pension plan expenses in TurboTax using these steps:
- Go into your business return.
- On the Here's your [XX] info screen, click the Add expenses box.
- On the Tell us about any expenses screen, under Less Common Expenses, click the radio button next to Employee pension plan, then click Continue at the bottom of the screen.
- Enter your contributions to your employees' retirement account on the next screen, Let's enter the employee pension plan expenses for your [XX] work.