Your home is worth $400,000 and you owe $250,000 on the mortgage. That's $150,000 in equity. A HELOC (Home Equity Line of Credit) lets you borrow against that $150,000 at relatively low interest rates - often 2-3 points above prime, or around 8-9% today. Compare that to a personal loan (10-15%), a credit card (21%+), or paying cash for a $30,000 kitchen renovation. A HELOC looks tempting: borrow $30,000 at 8.5% interest, and your monthly payment is roughly $210. But the cost you don't hear about upfront: you'll pay $39,000 in total interest over 20 years. That kitchen renovation costs $69,000 after interest. And if you take out the full $150,000, your monthly interest-only payment could exceed $1,000/month before principal kicks in.
HELOCs come in two flavors: a draw period (typically 5-10 years) where you pay interest-only and can borrow more anytime, and a repayment period (10-20 years) where the line closes and you amortize principal + interest. Many people take advantage of rock-bottom rates during the draw period, accruing interest-only payments they can afford. Then rates rise, the repayment period hits, and suddenly a $200/month interest-only payment becomes a $500/month principal-and-interest payment. The trade-off for the low rate: your home is collateral. If you can't pay, the lender forecloses. HELOC rates also adjust (usually quarterly or annually), so your payment isn't fixed - it could rise if prime rate climbs.
This calculator shows your monthly payment, total interest paid, and the amortization schedule for different loan amounts, rates, and terms. Test scenarios: What if I borrow $30,000 versus $50,000 for my payment? What if rates jump to 10%? If I pay an extra $100/month, how much sooner is it paid off? Compare against personal loan quotes and credit card APRs to see where HELOC wins - typically on larger amounts (over $20,000) and longer terms where the rate advantage compounds.
HELOC vs. Home Equity Loan: Key Differences
A HELOC (Home Equity Line of Credit) is flexible—you access funds as needed (like a credit card), paying interest only on what you use. A Home Equity Loan is a lump sum loan with fixed payments. HELOCs have variable interest rates (risky if rates rise); most home equity loans have fixed rates. HELOCs allow multiple draws; home equity loans are one payment. Choose HELOC for flexibility, home equity loan for rate certainty.
How Much Equity Do You Have?
Equity = Home value minus mortgage balance. If your home is worth ,000 and you owe ,000, you have ,000 equity (30%). Lenders typically allow you to borrow 80-85% of your home's value. If your home is worth ,000 and mortgage is ,000, maximum HELOC is ,000 - ,000 = ,000. This calculator assumes 80% LTV (loan-to-value) but check your lender's specific limits.
HELOC Rates and Terms
HELOC rates are variable, tied to Prime Rate or SOFR (Secured Overnight Financing Rate). When Fed rates rise, HELOC rates rise; when Fed rates fall, HELOC rates fall. Home equity loans have fixed rates (usually 1-2% higher than mortgages, lower than personal loans). In a rising-rate environment, fixed-rate home equity loans are safer. HELOCs are risky when rates are already high.
Tax Implications of HELOC Interest
HELOC interest is potentially tax-deductible if you use the funds for home improvement (not personal expenses). If you borrow ,000 on a HELOC at 9% (,500/year interest) and itemize deductions, you may deduct this interest. However, you must meet the home improvement requirement and have qualifying deductions above the standard deduction. Consult a tax professional on your specific situation.
Risks of HELOCs
Your home is collateral. If you default, the lender can foreclose. Rates are variable—if rates jump from 8% to 12%, your payment nearly doubles. Some lenders can freeze or reduce your available credit (risky if you relied on that flexibility). Rising home equity is your financial cushion; using it for non-essentials (vacations, cars) risks your home if finances deteriorate.