Hello

For social security you would need a w-4v and you can only select the percentage they withhold and not a dollar amount.  22% is the highest you can have withheld from Social security once filled out you just take it to your local social security office. https://www.irs.gov/pub/irs-pdf/fw4v.pdf

To take out a dollar amount you would need to do that from your retirement paln using a w-4p on step 4 part C you would put the dollar amount you want withheld https://www.irs.gov/pub/irs-pdf/fw4p.pdf and send it to the pension company

Hi!

To have federal income tax withholding taken out of your social security checks, you need to complete Form W-4V.  Your choices are limited to 7, 10, 12 or 22 percent of your monthly benefit withheld for taxes.   

You may have to do a few calculations to determine which percent of your monthly benefit to have withheld.

Please note, you will need to take the form to your local social security office.  Please see the links below for additional information.

https://www.ssa.gov/benefits/retirement/planner/taxwithold.html

https://www.aarp.org/retirement/social-security/questions-answers/taxes-withheld-ss.html

Regarding your statement about 1099's, I believe you are referring to estimated tax payments, (estimated tax payments are mailed in with Form 1040-ES each quarter). 🙂  If you start having enough federal income tax withheld from your social security each month, then you should avoid having to paying the quarterly estimated tax payments.