How the projection works
Your existing balance grows by compounding, and each monthly contribution (yours plus the employer match) is a payment into a growing annuity. The future value is the sum of the two:
FV = balance × (1+r)n + PMT × ( (1+r)n − 1 ) ÷ r
Where r is the monthly return (annual ÷ 12), n is the number of months (years × 12), and PMT is the total monthly contribution: (salary × your % + salary × match %) ÷ 12.
Worked example
A $20,000 balance, $60,000 salary, contributing 6% with a 3% match, 7% return, 30 years out:
Monthly contribution: (60,000 × 9%) ÷ 12 = $450.
Existing balance grows to: 20,000 × 1.00583^360 ≈ $162,000.
Contributions grow to: ≈ $549,000.
Projected total: ≈ $711,000.
Why the employer match matters
An employer match is free money — an instant return on your contribution. Contributing at least enough to capture the full match (here 3% of salary) is one of the highest-return moves in personal finance. Skipping it leaves guaranteed money on the table every year.
Note: this is a nominal projection. Real returns vary year to year, contributions may rise with raises, and IRS annual contribution limits apply ($23,000 employee deferral for 2024, plus catch-up if 50+).