Estimate how much you may be able to borrow against your home's equity and compare the payments and costs of a home equity line of credit. Enter your home's value, current mortgage balance and HELOC assumptions to model the draw and repayment periods. Results are estimates based on the assumptions you select, not a lender's approval or an offer of credit.
Estimate your potential credit limit, monthly payments and borrowing costs over the draw and repayment periods.
A home equity line of credit (HELOC) is a revolving credit line secured by the equity in your home. Unlike a traditional fixed home-equity loan that disburses a single lump sum upfront, a HELOC establishes an approved credit limit from which you can borrow, repay, and borrow again as financial needs arise.
Most HELOCs operate in two sequential phases: an initial draw period (typically 5 to 10 years) during which you can access funds and make interest-only or principal + interest payments, followed by a repayment period (typically 10 to 20 years) during which the line is closed to further borrowing and the remaining outstanding balance must be repaid in fully amortizing monthly payments.
Because HELOC interest rates are generally variable and pegged to benchmark rates like the U.S. Prime Rate, monthly payments can change over time. Furthermore, because a HELOC is secured by a junior mortgage on your residential property, failure to maintain required payments can put your home at risk of foreclosure.
Input your estimated home value and current first mortgage balance to establish your existing property equity.
Choose an 80%, 85%, 90% or custom combined loan-to-value limit to determine the maximum combined debt ceiling.
Specify your requested HELOC credit limit alongside the opening balance you plan to borrow immediately.
Select interest-only or principal + interest draw payments, term durations, interest rate, and closing fee treatment.
Review draw payments, repayment payments, payment changes at repayment, total interest, and total cash paid.
Test rate increases, additional future withdrawals, financing comparisons, debt consolidation, or potential tax effects.
Your borrowing capacity is determined by your home's appraised value and the combined loan-to-value (CLTV) limit enforced by the lender. CLTV measures the ratio of all home-secured loans (your existing first mortgage plus the requested HELOC line) relative to the property value.
Most lenders cap combined borrowing between 80% and 90% CLTV, though actual qualification also depends on your credit score, debt-to-income (DTI) ratio, employment stability, and property type.
Note: Unencumbered home equity (38%) is not identical to borrowable equity under an 80% cap. Lenders hold back 20% equity ($100,000 cushion), leaving $90,000 in additional borrowing room before the 80% ceiling is reached.
Understanding the distinction between the draw period and the repayment period is essential for managing your household budget and avoiding unexpected payment surprises.
During an interest-only draw period, the monthly payment covers only accrued interest calculated from your outstanding balance and periodic interest rate:
If you select principal + interest payments during the draw period, this calculator applies the greater of 1.5% of the credit limit or a 30-year amortizing payment schedule, ensuring steady principal paydown prior to repayment.
When the repayment period begins, the outstanding balance at the end of the draw period is amortized across the remaining months using the standard fixed-installment formula:
Because most HELOCs feature variable interest rates tied to market indices, your monthly payment can increase when the index rises. Furthermore, when an interest-only draw period ends and repayment begins, the addition of mandatory principal payments triggers a substantial payment change.
In our rate increase scenario tab, you can test how rate increases of +1, +2, or +3 percentage points (or custom hikes up to your contract's lifetime interest-rate cap) impact both draw and repayment payments.
An interest rate increasing from 8.00% to 10.00% represents an increase of two percentage points (2 pp), which is a 25% relative increase in interest charges. Our calculator uses precise percentage point modeling to reflect standard lending terminology accurately.
Borrowing through a HELOC involves charges beyond nominal interest rates. To provide a complete financial picture, our calculator separates:
Homeowners often draw funds over several years as home remodeling milestones are completed or college tuition installments come due. At the same time, making voluntary extra principal payments during the draw period immediately reduces the balance subject to compounding interest.
In the Additional withdrawals and extra payments tab, our calculation engine models future withdrawals at year 2, 3, 5, or 7 alongside extra monthly principal paydown. Interest savings are accurately compared against a strict baseline taking the exact same withdrawals without the extra payments.
Homeowners needing equity financing typically evaluate three distinct borrowing structures. Each has distinct financial scopes and risk profiles:
| Feature | HELOC | Home-Equity Loan | Cash-Out Refinance |
|---|---|---|---|
| Borrowing structure | Revolving credit line (draw as needed) | Lump-sum single disbursement | New mortgage replacing existing debt + cash |
| Interest rate type | Usually variable (tied to Prime) | Fixed for entire loan term | Fixed or adjustable primary mortgage |
| Repayment structure | Draw phase followed by amortizing repayment | Equal monthly principal + interest payments | Standard 15- or 30-year mortgage amortization |
| Impact on first mortgage | Preserves low first mortgage rate (second lien) | Preserves low first mortgage rate (second lien) | Replaces entire first mortgage at new rate |
| Closing costs | Often minimal or waived | Moderate closing costs (1% to 3%) | Highest closing costs (2% to 5% of total loan) |
Under current federal tax law (IRC § 163(h)(3) as amended by the Tax Cuts and Jobs Act), interest paid on a HELOC is not automatically tax-deductible simply because the debt is secured by your home.
To be potentially eligible for a federal mortgage interest deduction:
Important notice: A HELOC is a secured mortgage lien on your primary residence. Consolidating unsecured credit cards into a HELOC or borrowing beyond your sustainable repayment capacity puts your home at risk of foreclosure in the event of default.
A home equity line of credit (HELOC) is a revolving line of credit secured by your residential property. Unlike a fixed lump-sum loan, a HELOC establishes an approved credit limit from which you can borrow, repay, and redraw funds as needed during an initial draw period. Outstanding balances accrue interest, and all calculator results represent modeled estimates rather than an offer of credit or lender approval.
The estimated maximum HELOC credit limit is calculated by taking your estimated home value, multiplying it by the selected maximum combined loan-to-value (CLTV) limit, and subtracting your current first mortgage balance. For example, on a $500,000 home with an 80% CLTV limit ($400,000 maximum combined debt) and a $260,000 first mortgage, the remaining borrowing room is up to $140,000. Your actual credit limit is distinct from your initial draw amount—you only accrue interest on the balance actually borrowed.
The draw period is the initial phase—commonly 5 to 10 years—during which you can access credit up to your approved HELOC credit limit. Depending on the payment terms you select, monthly payments during this period may be interest-only (covering accrued interest without reducing principal) or principal + interest payments. Paying only interest keeps initial payments low, but leaves the entire borrowed balance to be repaid later.
When the draw period ends, the HELOC transitions into the repayment period—typically lasting 10 to 20 years. During repayment, you can no longer withdraw additional funds, and you must make fully amortizing monthly principal + interest payments to pay off the remaining balance by the end of the term. If you made interest-only payments during the draw period, your required monthly payment will increase substantially.
HELOC monthly payments can rise for two primary reasons: first, when the line transitions from an interest-only draw period to fully amortizing repayment; and second, because most HELOCs carry variable interest rates tied to the prime rate. If market benchmark rates climb, your annual interest rate and monthly payment will increase up to your contract's lifetime interest-rate cap. An initial low payment does not mean the total borrowing cost will remain low.
Beyond interest charges, HELOC borrowing costs may include upfront closing costs (such as appraisal fees, title search, recording fees, or application fees) and recurring charges such as annual maintenance fees or inactivity fees. Our calculator separates total interest from total fees so you can see the complete borrowing cost alongside total cash paid.
Yes. Because HELOC interest is calculated on your daily outstanding balance, making voluntary extra principal payments during the draw period immediately reduces the principal subject to interest charges. Accelerating principal paydown shortens the effective payoff schedule, reduces total interest over the modeled term, and lowers the required monthly payment when the repayment period begins.
Under IRC § 163(h)(3), HELOC interest is only potentially tax-deductible if the borrowed proceeds are used to buy, build, or substantially improve the primary or secondary home that secures the credit line. If funds are used for debt consolidation, college tuition, or living expenses, the interest is not deductible on federal tax returns. In addition, you must itemize deductions on Schedule A and remain within federal acquisition debt limits ($750,000 for married couples filing jointly). Consult a licensed tax advisor for your situation.
Neither product is universally better. A HELOC provides draw flexibility and lower initial interest-only payments, but carries variable-rate uncertainty and payment changes at repayment. A home-equity loan provides a single fixed lump sum with predictable, fixed monthly payments, but starts charging interest on the entire principal on day one. When comparing options, evaluate upfront fees, payment predictability, and total scheduled borrowing costs across your planning horizon.
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