Retirement income planning with pension and Social Security
For most future retirees, income will come from three main sources: personal savings (401k, IRA), a pension (if you're lucky enough to have one), and Social Security. This calculator combines all three to give you a realistic picture of your monthly retirement income, both in nominal dollars and adjusted for inflation.
How pension and Social Security fit in
Pensions provide guaranteed income for life. Social Security is also inflation‑adjusted and lifelong. Together they form a stable base. Your savings must cover the gap. In our example (age 45, retire at 65, live to 90, $150k saved, $800/month, 6% return, 2.5% inflation, $1,200 pension, $1,800 SS), total monthly income at retirement is about $5,200 nominal ($4,850 in today's purchasing power).
Key formulas
Future value of savings: FV = PV×(1+r)ⁿ + PMT×[((1+r)ⁿ−1)/r] (monthly contributions). Then at retirement, we spread the corpus over expected retirement years using systematic withdrawals: monthly from savings = total corpus / (retirement years × 12). Total monthly = savings withdrawal + pension + SS. Real income = total monthly / (1+inflation)^(years until retirement).
Example calculation: With numbers above, savings grow to ≈$751k. Over 25 retirement years (age 65‑90), monthly from savings = $751k / (25×12) ≈ $2,503. Add pension $1,200 + SS $1,800 = $5,503 monthly (before inflation adjustment). After 20 years to retirement, inflation reduces purchasing power: $5,503/(1.025^20) ≈ $3,360 real? Wait – we adjust only the income at retirement? Actually we show both nominal and real at retirement age. We'll display real at retirement age in summary.
Diversification matters: A mix of guaranteed income (pension/SS) and investment savings provides resilience.
Use these calculations as an informational basis only. Do not make financial, legal, or retirement decisions based solely on these results.
Frequently asked questions
How does Social Security affect retirement income? It provides a baseline inflation-adjusted income. You can include your estimated benefit (from SSA) in the calculator.
Can I rely only on pension and Social Security? Possibly if benefits are high, but many will need savings to cover expenses. Use this tool to see the gap.
How much savings do I need in addition to pension? It depends on your desired lifestyle. The calculator shows monthly from savings.
What withdrawal rate is safe? Here we use equal division over retirement years (simple). For more accuracy consider 4% rule.
How accurate are retirement income projections? They are estimates; actual returns, inflation, and lifespan vary. Recalculate periodically.