How this helper works
You bring the benefit estimate (from your SSA account — this tool doesn't connect to anything); it combines that income with portfolio withdrawals at your withdrawal rate and compares the total against your spending goal. The distinctive part: it also computes how much of your benefit is taxable, using the actual IRC §86 provisional-income formula — the same audited engine behind our Roth conversion planner.
Example calculation
A $2,100 monthly benefit ($25,200/yr) plus a $400,000 portfolio at 4% ($16,000) covers 66% of $62,000 spending. With $20,000 of other taxable income, provisional income is $20,000 + $12,600 = $32,600 — inside the 50% band — making about $3,800 of the benefit taxable.
Common mistakes to avoid
- Using the SSA's age-65 estimate while planning to claim at 62 — the check shrinks roughly 30%.
- Forgetting that up to 85% of benefits are taxable income — it also feeds Medicare IRMAA brackets.
- Treating Social Security as guaranteed real income: COLAs help, but the program's trust-fund projections imply possible ~2033+ cuts of roughly 20%+ under current law if Congress doesn't act.
Assumptions and limitations
Your own benefit estimate in, single-filer taxable formula, illustrative 22% tax rate on the taxable portion, no spousal coordination, no WEP/GPO offsets, no earnings test before full retirement age. This is an educational estimate, not a benefits projection.
Frequently asked questions
How is my Social Security benefit calculated?
SSA takes your highest 35 years of indexed earnings, applies bend-point formulas to the monthly average, and adjusts up or down for your claiming age relative to full retirement age (67 for those born in 1960 or later — roughly -30% at 62, +24% at 70). This tool deliberately skips that machinery: enter the estimate from your personal mySocialSecurity account, which runs the real formula on your actual earnings record.
How much of my Social Security is taxable?
It depends on 'provisional income' — your other taxable income plus half your benefits. Below $25,000 single / $32,000 joint, benefits are untaxed. In the middle band, up to 50% becomes taxable; above $34,000 / $44,000, up to 85%. Roth IRA withdrawals don't count toward provisional income, which is one reason Roth conversions in the years before claiming can permanently lower the tax on your benefits — the Roth conversion planner models this interaction year by year.
Will Social Security run out of money?
The trust fund projections have consistently shown a shortfall in the early-to-mid 2030s. That does not mean benefits vanish — payroll taxes keep flowing and would cover roughly three-quarters of scheduled benefits under current projections absent Congressional action. Prudent planning treats 75–100% of the scheduled benefit as the planning range rather than assuming either extreme.