HELOC
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Estimate your home equity line of credit limit, monthly payments during draw and repayment periods, and total interest cost — with equity visualisation and timeline chart.
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HELOC Calculator: Estimate Your Home Equity Line of Credit
A Home Equity Line of Credit (HELOC) is one of the most flexible and cost-effective borrowing tools available to homeowners — but it’s also one of the most misunderstood. Unlike a traditional loan, a HELOC gives you a revolving credit line secured against your home’s equity, which you can draw from and repay repeatedly during the draw period. This free HELOC calculator helps you estimate your available credit limit, monthly payments during both the draw and repayment phases, total interest cost, and the impact of variable rate changes — giving you the information you need to make a confident borrowing decision.
Quick example: A home worth $500,000 with a $300,000 mortgage balance and 80% LTV limit gives a HELOC credit limit of (500,000 × 80%) − 300,000 = $100,000. Drawing $60,000 at 7.5% with a 10-year draw period (interest-only) costs approximately $375/month during the draw phase. After the draw period, full amortisation over 20 years raises payments to approximately $483/month.
What Is a HELOC?
A Home Equity Line of Credit is a revolving credit facility secured by the equity in your home — the difference between your home’s current market value and the outstanding balance on your mortgage. Unlike a home equity loan (which provides a lump sum at a fixed rate), a HELOC operates like a credit card: you’re approved for a maximum credit limit and can draw any amount up to that limit at any time during the draw period, repay it, and draw again.
HELOCs typically have two phases: the draw period (usually 5–15 years) during which you can access funds and make minimum or interest-only payments, and the repayment period (usually 10–25 years) during which no further draws are permitted and the outstanding balance must be repaid in full through regular principal-and-interest payments.
How HELOC Credit Limits Are Calculated
Formula:
Available HELOC = (Home Value × LTV Limit %) − Outstanding Mortgage Balance
Most lenders cap combined LTV (mortgage + HELOC) at 80–90% of home value.
Example: $600,000 home, $350,000 mortgage, 85% LTV limit:
Available HELOC = ($600,000 × 85%) − $350,000 = $510,000 − $350,000 = $160,000
Draw Period vs Repayment Period Payments
| Phase | Duration | Payment type | Monthly payment ($60K at 7.5%) |
|---|---|---|---|
| Draw period | Typically 10 years | Interest-only (minimum) | $375/month |
| Draw period | Typically 10 years | Principal + interest | $707/month |
| Repayment period | Typically 20 years | Fully amortised P+I | $483/month |
| Repayment (rate +1%) | 20 years at 8.5% | Fully amortised P+I | $521/month |
The “payment shock” at the end of the draw period is one of the most significant risks of interest-only HELOC structures. Borrowers who make only interest payments for 10 years and then face full amortisation of the entire balance in a shorter repayment period experience a substantial jump in monthly obligations — often 30–60% higher than draw-period payments.
Variable Rate Risk
Most HELOCs carry variable interest rates tied to a benchmark rate (prime rate, SOFR, or equivalent). This means your monthly payments can increase significantly when interest rates rise — a critical risk factor to model before drawing on a HELOC.
- A $100,000 HELOC balance at 6% costs $500/month (interest-only). At 9%, the same balance costs $750/month — 50% more.
- During the 2022–2023 US rate hiking cycle, prime rate rose from 3.25% to 8.5%, causing HELOC rates to increase by more than 5 percentage points for many borrowers.
- Use the “Rate change simulation” toggle in this calculator to model how rising rates would affect your payments and total cost.
Smart HELOC Strategies
Pay principal during the draw period
Making principal payments during the draw period — not just interest — reduces your balance and dramatically cuts total interest. Even $200/month extra during a 10-year draw on $80,000 at 7.5% saves over $15,000 in total interest.
Consider converting to fixed rate
Many lenders allow you to convert some or all of your HELOC balance to a fixed-rate sub-account. This eliminates variable rate risk at the cost of slightly higher rates — valuable insurance against rising rate environments.
Plan for repayment payment shock
Budget for the jump in monthly payments when your draw period ends. Ideally, keep total debt service (mortgage + HELOC repayment) below 36% of gross monthly income to maintain financial stability.
Use for value-adding home improvements
HELOC funds used for home improvements may increase your home value — potentially restoring or exceeding the equity drawn. Kitchen remodels, bathroom renovations, and additional living space typically return 60–80% of cost in added value.
HELOC vs Home Equity Loan
| Feature | HELOC | Home Equity Loan |
|---|---|---|
| Disbursement | Revolving credit (draw as needed) | Lump sum upfront |
| Interest rate | Variable (usually) | Fixed |
| Draw flexibility | High — draw, repay, redraw | None — one-time draw |
| Payment consistency | Varies (interest-only during draw) | Fixed monthly payment |
| Best for | Ongoing expenses, uncertain amounts | Known one-time costs |
| Rate risk | Higher — variable rate exposure | Lower — locked at origination |
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