Each page here takes one household and works its federal return line by line: every income item, every deduction, each bracket slice and band, and the rule behind each line, linked to its entry on the sources page. The households are the hand-computed cases in the simulator’s own test suite, and every figure is produced by the simulator’s tax function when the page is built. For example, the first page’s retired couple owes $3,644 of federal tax on $142,000 of income, and the test suite checks that figure against the hand calculation.
Each example ends with what would change the result, computed the same way, and links to the guide that explains the rule and a calculator for trying your own numbers.
The worked examples
- Worked example: a retired couple’s federal return with a Roth conversion and capital gains
A couple, both 66, convert $80,000 and sell shares at a gain: every deduction, bracket slice and the 0% capital-gains band, line by line.
Topic: Taxes in retirement
- Worked example: the senior deduction and its phase-out
The same couple at three income levels and in the year after the deduction expires, showing exactly how the 6% phase-out shrinks it.
Topic: Taxes in retirement
- Worked example: how much of Social Security is taxable
The IRS worksheet for a single retiree, step by step, in the 85% band and the 50% band, and what changes for a married person filing separately.
Topic: Social Security
- Worked example: the widow’s penalty, from a joint return to a single one
The same $120,000 pension taxed on a joint return in the year a spouse dies and on a single return the year after, bracket by bracket.
Topic: Social Security
- Worked example: the 3.8% net investment income tax
A high-income couple with dividends, gains and Social Security: the 15% gains layer, then the NIIT on the smaller of investment income and income over the line.
Topic: Taxes in retirement
More
These examples show how the rules work. They are not financial, tax or investment advice. Real returns have details these examples leave out, so check the IRS instructions or ask a tax professional before you act. See the disclaimer.