10. Ignoring Medicare Part B Premium Deductions

Social Security and Medicare are deeply intertwined. Once you enroll in Medicare at age 65, your Medicare Part B premiums are automatically deducted from your monthly Social Security checks. Many retirees build their budget spreadsheets based on the gross Social Security estimate provided on their statements, failing to realize the cash deposited into their bank account will be much lower.

Furthermore, if you have a high income in retirement due to capital gains, property sales, or large required minimum distributions (RMDs) from retirement accounts, you will be hit by the Income-Related Monthly Adjustment Amount (IRMAA). IRMAA surcharges can drastically increase your Medicare Part B and Part D premiums. Because these inflated premiums are siphoned directly out of your Social Security payment, wealthy retirees often experience a jarring realization when their Social Security check shrinks significantly to cover mandatory healthcare surcharges. Navigating these rules requires proactive research via resources like Medicare.gov well before you file your final pre-retirement tax returns.