Hello, thank you for your question. The amount taxed on social security depends on how much social security benefits received and total income from all sources. I am going to include a couple helpful links. The first is from the irs and how social security is taxed. The second is a TurboTax article that explains a little more detail. The third is refund estimator. This will help you see what your tax situation will look like based on estimates so you can pick the proper witholdings. I hope this helps and I answered your question.
https://www.irs.gov/faqs/social-security-income
https://ttlc.intuit.com/turbotax-support/en-us/help-article/retirement-benefits/social-security-inco...
https://turbotax.intuit.com/lp/ppc/2541?srqs=null&cid=ppc_gg_nb_stan_all_na_Calculator-CalculatorEst...
