You said My husband retired in June 28, 2024 and is working part time and will receive a 1099 at the end of the year. How do we pay in for social security and medicare?

[xmasbaby0]

If your spouse is self-employed for part of the year then he will pay self-employment tax for Social Security and Medicare for his self-employment income.  He can pay estimated tax beforehand, or pay at tax time.   Your post implies that up until late June he had a W-2 job with tax withheld.

If you have self-employment income for which you will pay self-employment tax for Social Security and Medicare,  you will need to use online Premium software or any version of the CD/download so that you can prepare a Schedule C for your business expenses.

https://ttlc.intuit.com/questions/2926899-how-does-my-side-job-affect-my-taxes

https://ttlc.intuit.com/turbotax-support/en-us/help-article/form-1099-nec/1099-nec/L5qTsBiSe_US_en_U...

https://ttlc.intuit.com/community/self-employed/help/how-do-i-report-income-from-self-employment/00/...

https://ttlc.intuit.com/community/self-employed/help/what-is-the-self-employment-tax/00/25922

https://ttlc.intuit.com/questions/2902389-why-am-i-paying-self-employment-tax

https://ttlc.intuit.com/questions/1901340-where-do-i-enter-schedule-c

https://ttlc.intuit.com/questions/3398950-what-self-employed-expenses-can-i-deduct

https://blog.turbotax.intuit.com/self-employed/self-employed-tax-deductions-

calculator-2021-2022-50907/

https://ttlc.intuit.com/questions/1901110-do-i-need-to-make-estimated-tax-payments-to-the-irs

https://turbotax.intuit.com/tax-tools/calculators/self-employed/

[pk]

@mbbennett81 , agreeing with  my colleague @xmasbaby0 , excellent answer and noting that your husband would be receiving a 1099-NEC  from his part-time work,  would mean that he will have to report this 1099-NEC income on Schedule-C  ( just like a self-employed or  Sole proprietor  business  ).  

On schedule-C, you show your gross income  and are allowed to deduct  allowable expenses ( like travel/mileage etc. i.e. expenses that are  usual and necessary )  to maintain this stream of income.   Incomes  over 400 ( if my memory serves my right )  will trigger  Schedule-SE  ( this is for Social Security & Medicare contribution at 15.3% ) fill out.

Note that  while the  tax on the 1099-NEC income . needs to be up to date  via   quarterly estimated payments, there is no such requirement for the  SECA  ( equivalent to the FICA   mentioned above ).

Is there more one of us can do for you ?

[TomD8]

Since your husband will be receiving a 1099-NEC at year's end, the IRS will regard him as a self-employed "business", also known as a "sole proprietor."  As such he will have to report that income on Schedule C, which will be part of his regular tax return.  His self-employed income will be subject to both income tax and self-employment tax.  The latter covers his Medicare & Social Security tax and is reported on Schedule SE.  

When you enter his 1099-NEC into TurboTax, the program will automatically generate both Schedule C and Schedule SE for you and will calculate the taxes due.

Your husband should keep track of the business expenses associated with his self-employment, because he can deduct these expenses from his self-employment income.  He pays taxes only on the net income after expenses.  The expenses are deducted on Schedule C.

Ordinarily no taxes are withheld on a 1099-NEC.  Most self-employed people thus have to pay quarterly estimated taxes.  Here's a TurboTax help article on that:

What are federal estimated taxes? (intuit.com)

If you live in a state with an income tax, you might have to pay estimated taxes to the state as well.