Self-employed retirees who earn money from side hustles face a painful tax reality. They pay both the employee and employer portions of Social Security tax, totaling 15.3 percent of net earnings instead of the 7.65 percent that W-2 employees contribute.

Here's how it works. When you work for an employer, you pay 6.2 percent toward Social Security and 1.45 percent toward Medicare. Your employer matches that amount. Self-employed people must cover both sides themselves through self-employment tax. The IRS expects you to send quarterly estimated tax payments based on your projected income.

This applies even if you already collect Social Security benefits. The Social Security Administration doesn't stop your checks if you earn money as a freelancer or run a small business. However, if you're under full retirement age, the SSA reduces your benefits by one dollar for every two dollars you earn above a certain threshold. In 2024, that threshold sits at $23,400 annually. If you're in the year you reach full retirement age, different rules apply with a higher earnings limit.

The self-employment tax burden hits harder than many retirees expect. A side hustle generating $30,000 in profit creates roughly $4,590 in self-employment taxes. You also owe regular income tax on that same amount, potentially pushing you into a higher tax bracket.

Retirees should track every business expense carefully. Deducting home office costs, equipment, supplies, and mileage reduces your net profit and lowers both self-employment and income taxes. You can deduct half of your self-employment tax as well, which provides modest relief.

Planning matters. Stagger income timing if possible, work with a tax professional to estimate quarterly payments, and consider whether a side hustle pencils out after taxes. Some retirees find that