How taxes are modeled: US FEDERAL income tax uses the real 2026 IRS bracket schedule for your filing status — standard deduction plus the age-65 addition, long-term capital-gains brackets, the net investment income tax, and Social Security inclusion — indexed for bracket creep each year, not a flat rate. Each destination applies its own tax schedule on retirement income — a full progressive schedule wherever one has been modeled, with the US treaty credit stated per destination. US STATE tax is the one flat figure: a single rate you select, exact for flat-tax states and an approximation for progressive ones. RMDs use the IRS Uniform Lifetime divisor from age 75. Withdrawal order draws from brokerage first, then whichever of Traditional/Roth carries the lower effective tax rate under your current settings. Survivor Social Security uses a simplified "higher of the two benefits" rule. Treat this as a planning compass, not a filed tax return or immigration filing.