Social security benefits - may be partly taxable depending on other taxable income.
Here is a simple test.
- take a half of social security benefits
- PLUS other taxable income
- if the total is less than $25000 (for singles) or $32,000 (for married couples filing jointly) - none of social security benefits would be taxable
- if the total is more than the threshold - we would need to use a special worksheet to determine the taxable portion.
So far - in your situation - if $18,000 social security benefits is your ONLY income - none is taxable and your your tax liability would be ZERO.
But when your start a part time job earning $1000 per month - or $12,000 per year - that will be your taxable income
Your social security benefits $18,000 / 2 + $12,000 = $21,000 - that is less than $25k - and none of social security benefits would be taxable.
But if your earnings would be $2000 per month - or $24,000 per year - the situation could be different - and a part of social security benefits becomes taxable.
Let me know if you need any help to evaluate your situation.