In conjunction with your other other social security income tax payments, you must include tax-exempt interest when you are preparing your social security income tax preparation. Also, if you are married and filing a joint return, you have to use the total of your spouse's income, your income (other than Social Security), plus your social security and equivalent tier 1-railroad retirement benefits when figuring the taxable portion of the benefits. There is a worksheet in the Form 1040 or Form 1040A in the instruction book for base amounts and other taxable information. There are instances where you're SSI and/or your Disability Benefits are taxable.
In regards to SSI income tax preparation, you must first look at the base amount you are filing against the total of one half of your social security payments in addition to all of your other income.