When IRA distributions are taxable
Traditional IRA distributions are taxable to the extent they exceed your basis (after-tax contributions tracked on Form 8606). Roth IRA qualified distributions are entirely tax-free; non-qualified Roth distributions follow ordering rules — contributions first (always tax-free), then conversions (each with its own five-year clock for the 10% penalty), then earnings (taxable plus possibly penalized).
Early-distribution tax
Distributions before age 59½ generally trigger a 10% additional tax under Section 72(t). Many exceptions apply: substantially equal periodic payments, first-time home purchase up to $10,000, qualified higher education expenses, unreimbursed medical above 7.5% of AGI, total and permanent disability, birth or adoption distributions up to $5,000, and many more.
Required minimum distributions
Traditional IRA owners must begin taking RMDs by April 1 of the year following the year they turn 73 (75 for those born in 1960 or later, under SECURE 2.0). Roth IRA owners are not subject to RMDs during their lifetime. The penalty for missing an RMD is 25% (reduced from 50% under SECURE 2.0; further reduced to 10% if corrected within a "correction window").
Inherited IRAs
Beneficiaries of IRAs face complex post-SECURE rules. Most non-spouse beneficiaries of accounts owned by someone who died after 2019 must withdraw all funds within 10 years; "eligible designated beneficiaries" (spouse, minor child, disabled, chronically ill, less-than-10-years-younger) get a stretch over life expectancy. Spousal beneficiaries can roll into their own IRA.
Net unrealized appreciation
Special rules let you take a lump-sum distribution of employer stock from a 401(k) and pay ordinary income tax only on the basis, with the appreciation taxed at long-term capital gains rates when sold. NUA is reported on a separate worksheet, not directly on Form 1040.
How to find what you need quickly
Reading an IRS publication straight through is rarely the right move; using it as a reference is. Open the PDF, jump to the table of contents, identify the chapter that matches your facts, and skim the worked examples at the end of that chapter first — they usually answer 80% of practical questions. The detailed rules in the body of the chapter then make sense in the context of an example. The publication's index, while less polished than a commercial tax-research database, is searchable in any PDF reader with Ctrl+F and surfaces the exact paragraph you need in seconds.