Disability Insurance Calculator

Disability insurance replaces a portion of your income if you become unable to work due to illness or injury. The core calculation determines how much monthly benefit you need, how long it should last, and how much the premium will cost relative to your income.

Benefit need formula: Monthly Benefit Needed = Monthly Take-Home Pay − Passive Income − Reduced Expenses While Disabled

Coverage ratio: Most disability policies replace 60–70% of pre-disability gross income (the non-taxable benefit rule means 60–70% gross ≈ full take-home after tax).

Income replacement formula: Target Benefit = Gross Monthly Income × Replacement Ratio (0.60–0.70)

Elimination (waiting) period impact on emergency fund: Emergency Fund Needed = Monthly Expenses × Elimination Period (months)

Common elimination periods: 30, 60, 90, 180, or 365 days. Longer elimination periods = significantly lower premiums.

Premium cost benchmarks:

• Short-term disability (STD): 0.3–0.5% of annual salary per year
• Long-term disability (LTD): 1–3% of annual salary per year
• Typical rule: budget 1–3% of your gross annual income for comprehensive coverage

Policy definitions — critical terms:

• Own-occupation: Pays if you cannot perform YOUR specific job (best coverage; most expensive)
• Any-occupation: Pays only if you cannot work ANY job (cheapest; hardest to qualify for benefit)
• Benefit period: How long benefits are paid — 2 years, 5 years, or to age 65/67
• COLA rider: Cost-of-living adjustment — benefit increases with inflation during a long claim

Probability context (US data):

• 1 in 4 workers will experience a disability lasting 90+ days before age 65
• Average long-term disability claim lasts 34 months (nearly 3 years)
• Most disabilities are caused by illness (cancer, heart disease, musculoskeletal) — not accidents

Worked example: Gross monthly income: $7,500. Take-home: $5,600. Fixed monthly expenses: $4,000.

• Target benefit (60%): $7,500 × 0.60 = $4,500/month
• Elimination period: 90 days → emergency fund needed: $4,000 × 3 = $12,000
• Annual premium (2% of $90,000 salary): $1,800/year = $150/month
• Benefit period: to age 65 (own-occupation, with COLA rider)

A $150/month premium protecting $4,500/month in income for potentially 30+ years is among the best risk-management purchases a working professional can make.