Retirees could be quietly losing thousands of dollars by parking savings in the wrong places, and most of these mistakes have nothing to do with the stock market.

• Money sitting in fintech apps (not actual banks) isn't automatically FDIC-protected — if the middleman partner bank fails, like Synapse did in 2024, customers can get locked out for months or lose funds entirely.
• Large amounts of cash kept at home earn nothing, lose value to inflation, and are barely covered by most home insurance policies if stolen.
• Adding an adult child's name to a bank account can backfire — the money can become exposed to that child's creditors or lawsuits, and it may bypass a will entirely after death.
• Forgotten bank accounts and CDs can get swept into state unclaimed-property programs, and CDs often auto-renew at much lower rates than people realize.
• Cash left in low-interest savings accounts or brokerage sweep accounts quietly costs people thousands a year in lost interest compared to higher-yield options.

Outlook: Seniors who review where their cash sits — checking bank insurance status, old accounts, CD rates, and savings yields — stand to recover real money, but need to weigh taxes, Social Security, and Medicare effects before chasing higher rates.