SmartAsset and Yahoo Finance LLC may earn commission or revenue through links in the content below. If you have an individual retirement account (IRA), 401(k) or similar tax-deferred retirement savings account, your withdrawals will be taxed as ordinary income (and can trigger those Social Security taxes mentioned above). You'll need to account for these taxes or look for ways to reduce them in retirement. 1. Not Accounting for Social Security Taxes Did you know that you may need to pay income taxes on your ...