Self employment tax exemption - Form 4029

[c-s-n]

How do I exempt self employment income from self employment/social security tax? I have a 4029 exemption.

[IreneS]

Form 4029 does not need to be filed with your income tax return.  Go to www.irs.com to get the form.  Fill it out and then mail it to the address specified in the form instructions.  [TurboTax does not include this form.]

Since you already have an approved Form 4029, you'll need to file your return by mail rather than e-file to claim your exemption. 

According to IRS Publication 517:

If you filed Form 4029 and received IRS approval not to be taxed on those earnings, and you don't have any other income subject to SE tax, don't file Schedule SE (Form 1040). Instead, enter “Form 4029” on the dotted line next to Schedule 4 (Form 1040), line 57.

It is not possible to do this in the online versions of TurboTax.  You can, however, download the return you prepared online into the CD/Download version  [instructions at the bottom of this answer]. 

To indicate your exemption in TurboTax CD/Download, please follow these steps:

1. Go into Forms Mode by clicking on the Forms icon at the top right of the screen.
2. In the Forms in My Return list,  click Schedule 4 to open it.
3. When that form populates, double-click on the line 57 amount. This will take you to the 1040 Worksheet.
   
4. Click on the amount on line 57, then Ctrl+D which will turn the amount red and enter zero on that line.
   
5. When you print out the tax forms, write “Form 4029”  on the dotted line next to Schedule 4, line 57.

To download a return you prepared online to your computer please follow these steps:

1. While in your return, click Tax Tools > Tools (in the black bar at the left of your screen)
2. In the Tools Center, click Save your 2018 return to your computer.
3. The file will automatically download to the Downloads folder on your computer.
4. Once you've installed TurboTax you can move the file from Download to: C:\Users\[your name]\Documents\TurboTax
   

[Edited 4/8/2019 6:55 am PDT]

[c-s-n]

I already have an approved 4029. How do I mark self employment income as social security tax exempt?

[c-s-n]

From the 4029 instructions:

"How to show exemption from self-employment taxes on Form 1040. If the IRS returned your copy of Form 4029 marked “Approved,” write “Exempt—Form 4029” on the “Self-employment tax” line."

How do I do this with TurboTax?

[IreneS]

I've edited my original answer to include instructions on indicating your exemption in TurboTax.