IRA Projection v.9

IRA Projection Tool — How to Use

What is this?

A visual model for understanding how a pre-tax IRA grows or depletes over time — and what that means for your taxes. It shows how Required Minimum Distributions (RMDs) can force income you may not need, and lets you explore different futures by adjusting growth rates, withdrawal rates, and outside income sources.

This tool was built specifically to model large IRA balances and the cascading RMD effects that can follow unexpected growth. Once an IRA grows large enough, RMDs can push you into higher tax brackets, trigger IRMAA surcharges, and — for a surviving spouse filing single — cause a severe "Widow's Tax" cliff. This tool makes those dynamics visible.

What can I explore?

• Two withdrawal periods — Model a higher-spend early retirement followed by reduced withdrawals later (or vice versa). The "Withdrawal target" line steps between rates at their configured start ages.
• Two Social Security incomes — Enter each spouse's SS amount (in today's dollars) and the age at which it begins, expressed relative to your current age. Both grow with inflation from their start years and are fully additive.
• Roth conversion headroom — With SS and other income set, raise your withdrawal above lifestyle needs. The gap between the Total Income line and the next bracket ceiling shows how much you could convert annually.
• MFJ vs. Single ("Widow's Tax") — Toggle the filing-status switch. Bracket thresholds roughly halve when filing single, often triggering IRMAA tiers that were previously clear.
• Inflation's toll — Switch to Today's $ mode to see the gap between the nominal IRA balance and its real purchasing power.

Left Panel — Inputs

• Current age — projection begins at this age.
• Withdrawal 1 start age / amount — Period 1 withdrawals begin at this age; amount in today's dollars, grown with inflation each year.
• Withdrawal 2 start age / amount — Period 2 takes over at this age (must be ≥ Period 1 start, ≤ 85). If both start ages are equal, Period 2 applies.
• Starting balance / Annual growth — today's pre-tax IRA balance and expected nominal annual return.
• Inflation rate / Years to project — assumed annual inflation and projection window.
• My SS / Spouse SS — each person's Social Security (or other inflation-linked) income in today's dollars, with a separate start age. Ages are relative to your current age — e.g., if you are 50 and your spouse is already collecting, set Spouse SS start age to 50. Both streams are inflation-adjusted and fully additive.
• Fixed add'l income — income fixed in nominal terms: pension, interest, dividends, cap gains.

The Total Income line includes all sources (IRA + SS + fixed). Threshold lines show raw inflated amounts so you can see directly which bracket your total income falls in.

Withdrawal Logic

• Each year: balance grows → RMD calculated (age ≥ 75) → target = active withdrawal period amount × inflation factor → IRA withdrawal = min(available balance, max(target, RMD)).
• No IRA withdrawal before Period 1 start age.
• Once the IRA is exhausted, IRA withdrawals stop — Total Income continues from SS and fixed sources only.
• SECURE 2.0: RMDs start at 75 for those born after 1958.

Calculations

• RMD — prior year-end balance ÷ IRS Uniform Lifetime Table factor (age 75+, SECURE 2.0, born after 1958).
• IRA withdrawal — min(available balance, max(inflation-adj target, RMD)); zero before Withdrawal 1 start age.
• Total income — IRA withdrawal + My SS (if active) + Spouse SS (if active) + fixed income.
• SS amounts — entered in today's dollars; inflation-adjusted from their start year before contributing each year.
• Thresholds — bracket floors and IRMAA tiers sourced from retirement_optimizer_taxdata.js (2026 federal tables). The standard deduction is added automatically and age-adjusted at 65 (one stdbump applied for MFJ — assumes one spouse at 65; actual may be higher if both spouses are 65+). For example, MFJ income enters the 10% bracket at the $32,200 standard deduction — only income above that is taxable. Bracket fills extend to the next bracket line — click any legend item to toggle.
• NIIT — not inflation-indexed; stored as a negative floor and plotted as a flat nominal line in Future $ mode.
• "Funded until" — last year the IRA balance fully covers the active inflation-adjusted withdrawal target; the final projected year if never depleted.
• Amber table rows — RMD exceeds your target withdrawal. Red rows — IRA depleted.

Tax, IRMAA & NIIT Threshold Lines

• Colored bands — federal income tax brackets. Each filled band represents one bracket's income range.
• Purple lines — Medicare IRMAA surcharge tiers. These are cliffs: one dollar over the line triggers the full annual surcharge.
• NIIT line — Net Investment Income Tax threshold ($250k MFJ / $200k Single + std deduction). A 3.8% surtax on net investment income above this level. Unlike other thresholds, NIIT is not indexed to inflation and plots as a flat line in Future $ mode.
• Threshold amounts are bracket floors from the 2026 tax tables with the standard deduction added automatically. The std deduction is age-adjusted at 65 (MFJ base $32,200 + $1,650 per spouse at 65; Single base $16,100 + $2,050 at 65). For example, MFJ income is first taxed at 10% above the $32,200 standard deduction — the first $32,200 is fully sheltered. Thresholds are grown with inflation each year (except NIIT, which is flat in nominal terms).
• Click any legend item to show or hide it.

Metric Cards

• Nominal / Real bal — IRA balance at end of projection in future and today's dollars.
• Peak RMD — largest required minimum distribution over the projection period.
• Funded until — last year the IRA fully covers the active withdrawal target; the final projected year if never depleted.
• Total IRA Drawn — cumulative sum of all IRA withdrawals over the projection window (nominal).
• Total Income — cumulative sum of all income sources (IRA + My SS + Spouse SS + fixed) over the window (nominal).

Limitations

• Growth is constant here; markets are not. A single annual rate is a useful fiction.
• Tax law changes. Brackets, standard deductions, and IRMAA thresholds are all subject to legislation.
• Net spendable income is not calculated. The tool shows gross income and bracket placement, not after-tax cash.
• No state taxes. Most states tax IRA withdrawals; some exempt Social Security.
• No external assets. Brokerage accounts, savings, and real estate are not modeled.
• Longevity is unknown. Neither your lifespan nor your spouse's is factored in.

Tips

• Amber rows in the table = RMD exceeds your target withdrawal. Red rows = IRA depleted.
• For IRMAA planning: qualified charitable distributions (QCDs) do not count toward MAGI.
• SS amounts are in today's dollars — no need to pre-inflate. The tool adjusts them before they begin.
• Try Today's $ mode to see whether your real purchasing power holds steady over time.

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