HELOC Payoff Calculator: Time to Clear a Line Balance
See how long a home equity line of credit takes to clear at a fixed monthly payment, and how much interest the balance accrues along the way.
Adjust the inputs and select Calculate for a full breakdown.
Year-by-year payoff schedule
Compare Common Scenarios
How the numbers shift across typical situations for this calculator:
| Scenario | Time to pay off | Total interest | Total paid |
|---|---|---|---|
| $25k · 9.5% · $600/mo | 4y 3m | $5,456.63 | $30,456.63 |
| $15k · 8% · $400/mo | 3y 8m | $2,318.67 | $17,318.67 |
| $60k · 10% · $1k/mo | 7 years | $23,524.79 | $83,524.79 |
| $8k · 7.5% · $300/mo | 2y 6m | $778.94 | $8,778.94 |
How This Calculator Works
Enter the HELOC balance, its interest rate, and the monthly payment you plan to make. The calculator works through the balance month by month and reports the payoff time and the total interest. HELOC rates are usually variable; rerun if your rate moves.
The Formula
Debt Payoff Time
B = balance, P = fixed monthly payment, r = monthly rate (APR ÷ 12), n = months to clear
Worked Example
A $25,000 HELOC balance at 9.5% paid at $600 a month clears in 51 months. Interest over that period adds about $5,457 on top of the amount drawn from the line.
Key Insight
A HELOC's variable rate tracks the prime rate, so payment plans can be derailed by a rate rise. Locking in a fixed payment well above the interest-only minimum builds in a buffer and forces principal down.
The draw period vs repayment period: a HELOC's two phases
A HELOC has two distinct phases that fundamentally change the payment math. DRAW PERIOD (typically 10 years): you can withdraw up to your credit limit at any time. During draw period, minimum payments are usually INTEREST-ONLY — meaning if you owe $50,000 at 9%, your minimum payment is just $375/month (interest only) with NO principal reduction.
REPAYMENT PERIOD (typically 10-20 years after draw ends): no more draws. The outstanding balance amortizes into principal + interest payments — often DRAMATICALLY higher than what you've been paying during draw. The 'payment shock' at the end of the draw period catches many HELOC borrowers off guard.
Worked example: $50k HELOC at 9%, 10-year draw + 20-year repayment. During draw: $375/month interest-only. After draw at $50k still outstanding: $50,000 amortized over 240 months at 9% = $450/month. Not too bad. But if you DRAW THE FULL $100k LIMIT by year 9: amortized payment becomes $900/month — DOUBLE the previous interest-only $750/month, with no exit option. Plan repayment-phase payments from the day you sign.
Variable rate exposure: the rate-shock scenario
Most HELOCs are VARIABLE rate, indexed to the Prime Rate + margin. Prime in 2026 is ~7.75%; HELOCs typically Prime + 0-2.5% = 7.75-10.25%. The rate can ADJUST monthly or quarterly based on Prime movements.
Rate shock scenario: HELOC originated in 2020 at Prime (3.25%) + 1% margin = 4.25% — very cheap. By 2024, Prime had risen to 8.5%, making the same HELOC 9.5%. Payment on $50k interest-only: was $177/month, became $396/month — more than double, with no advance warning. Many homeowners who treated cheap HELOCs as 'free money' faced sticker shock.
Risk mitigation: (1) HELOCs typically have lifetime rate caps (often 18%) — high but limits worst case. (2) Convert balance to fixed rate via HELOC 'lock-in' feature offered by some lenders — locks portion of balance at fixed payment for term. (3) Aggressive principal payoff during low-rate periods to minimize exposure when rates rise. (4) Establish HELOC for emergencies but minimize ongoing balance — the lower your average balance, the smaller the rate-risk exposure.
Strategies to pay off HELOC aggressively
Once you decide to pay off, several strategies maximize speed. STRATEGY 1: increase monthly payment significantly during draw period (your minimum is interest-only, so any extra goes to principal). Adding $200-500/month to interest-only during draw period dramatically reduces the eventual repayment-phase balance.
STRATEGY 2: refinance to fixed-rate home equity loan. Convert variable HELOC to fixed HEL at current rates — eliminates variable-rate exposure. Math: HEL at 9% fixed for 10 years on $50k = $633/month, total interest $26k. Variable HELOC remaining at 9% but could rise — riskier even if currently same rate.
STRATEGY 3: cash-out refinance of primary mortgage. If primary mortgage rate is below current rates, cash-out refi rolls HELOC balance into a single fixed-rate mortgage. Math depends heavily on relative rates: works if primary mortgage rate is significantly above current rates (refinance both at lower rate); fails if primary is below current rates (consolidation rate higher than primary). Run the numbers carefully — 'consolidation' isn't free if it raises your primary mortgage rate.
HELOC payment phases — interest-only vs amortizing
$50,000 HELOC balance at 9% APR. Compares interest-only payment during draw period vs amortizing payments during repayment.
| Phase / Strategy | Monthly payment | Years to pay off | Total interest paid |
|---|---|---|---|
| Draw period (interest-only) | $375 | Forever (no payoff) | Indefinite |
| Repayment, 20-year amort | $450 | 20 yr | $57,933 |
| Repayment, 10-year amort | $633 | 10 yr | $25,964 |
| Interest-only + $200/mo to principal | $575 | 13 yr | $26,440 |
| Interest-only + $500/mo to principal | $875 | 6.8 yr | $15,400 |
Interest-only forever is the 'trap' — you never pay down principal. Adding any principal during draw period materially reduces both total interest and avoids payment shock at repayment phase start.
Frequently Asked Questions
What is a HELOC?
A home equity line of credit is a revolving credit line secured by your home. You draw on it as needed, pay interest on the balance, and can repay and redraw within the draw period.
Are HELOC rates variable?
Usually yes. Most HELOC rates track the prime rate plus a margin, so the rate moves over time. This calculator models one steady rate as an estimate.
What is interest-only on a HELOC?
During the draw period, the minimum payment is often only the month's interest, with no principal repayment. The balance stays the same until you pay above the minimum.
What happens at the repayment period?
After the draw period, the loan typically enters a fixed repayment phase with a larger payment that includes principal. The payoff time depends on that payment schedule.
Is HELOC interest tax-deductible?
Sometimes — only when the line is used to buy, build, or substantially improve the home that secures it. Rules change, so confirm with a tax professional.
References & Authoritative Sources
- CFPB — Consumer Financial Protection Bureau — HELOC guide and payment shock warning · consulted May 31, 2026 · Federal consumer protection — HELOC draw/repayment phases, payment shock, foreclosure risk
- Federal Reserve — Prime Rate History — Prime rate tracking for HELOC pricing · consulted May 31, 2026 · Authoritative source — current US Prime Rate (basis for most HELOC rates)
- Truth in Lending Act — HELOC disclosures — HELOC required disclosures under Regulation Z · consulted May 31, 2026 · Federal regulation — HELOC disclosure requirements, rate cap requirements
Related Calculators
Data Sources & Benchmarks
This calculator draws on 3 independent, dated sources. The starting values for interest rate are taken from the benchmarks below and refresh whenever the snapshots are updated.
Methodology & Review
The payoff is simulated month by month: interest is charged on the balance, the fixed payment is deducted, and months are counted until the balance clears. HELOC rates are usually variable; this models a single steady rate.
Updated