Compare investing in a brokerage account versus accelerating mortgage payoff
Original Loan Terms
$
%
Monthly P&I
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Months Paid
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Expected Balance
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Remaining
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Current Status
Scenarios run forward from your current balance and remaining term.
$
$
Existing investments — grows in both scenarios
$
To invest OR pay extra principal
Lump Sum Payments
Applied to mortgage (A) or brokerage (B) — within first 5 years from today
Investment Assumptions
%
%
%
IL flat rate — gains taxed as ordinary income
%
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Enter your loan details above
A — Pay Off Early
B — Invest the Extra
Mortgage Paid Off
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Mortgage Paid Off
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Total Interest Paid
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Total Interest Paid
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Brokerage Account Value
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Brokerage Account Value
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Net Financial Outcome
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Net Financial Outcome
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How the scenarios work
Scenario A: Extra monthly amount + lump sums go toward mortgage. Once paid off, the full P&I + extra are invested monthly.
Scenario B: Extra monthly amount + lump sums go into brokerage from the start of the comparison. Mortgage pays down on the standard payment — if you're ahead of schedule it retires early, and the freed P&I is then invested too.
Net Worth Growth (equity + investments)
Remaining Mortgage Balance
Why the spread matters
Simplified model: constant annual returns (no sequence-of-returns risk), long-term capital gains on all gains, no dividend tax drag. State tax on gains defaults to Illinois's flat 4.95% (gains taxed as ordinary income; IL allows no mortgage interest deduction, so the itemized deduction is federal-only). Current brokerage balance is treated as cost basis — only growth from today forward is taxed. Historical returns are nominal. "Last 12 mo, actual sequence" replays the real S&P 500 monthly total returns from Aug 2025–Jul 2026 (dividends reinvested, SPY proxy) on a repeating loop. Not financial advice.