HELOCs Explained: How Draw Periods, Repayment, and Variable Rates Work

A home equity line of credit, or HELOC, is a form of revolving credit that lets homeowners borrow against the equity they have built up in their property. Unlike a home equity loan, which delivers a single lump sum with fixed payments, a HELOC works more like a credit card: you get approved for a maximum credit limit, draw funds as needed, and pay interest only on the amount actually borrowed. Because the loan is secured by the home, HELOCs typically carry lower interest rates than unsecured personal loans or credit cards, but they also put the house itself at risk if payments are not made.

Two Distinct Phases: Draw and Repayment

Every HELOC is structured around two periods, and understanding the transition between them is essential. The draw period, commonly ten years, is when the borrower can withdraw funds up to the credit limit, repay them, and withdraw again, similar to a revolving account. Many lenders allow interest-only payments during this phase, according to the Consumer Financial Protection Bureau, which means the outstanding principal does not necessarily decrease unless the borrower chooses to pay down more than the minimum.

Once the draw period ends, the HELOC enters the repayment period, often spanning ten to twenty years. At this point, the ability to draw new funds typically stops, and the loan converts to fully amortizing payments that include both principal and interest. Because payments during the draw period may have covered only interest, the shift to amortizing payments can produce a significant increase in the monthly bill, sometimes called payment shock. Borrowers should ask their lender for the exact math on how payments will change before signing.

Why Rates Move

Most HELOCs carry variable interest rates tied to a benchmark index, frequently the prime rate published based on the federal funds rate set by the Federal Reserve's Federal Open Market Committee, plus a margin set by the lender. When the Fed adjusts its target range, the prime rate typically follows within a short window, and HELOC rates adjust accordingly, usually on a monthly or quarterly basis depending on the loan agreement. This means the interest cost on a HELOC can rise even if the borrower has not drawn any additional funds, simply because the underlying index moved higher. Some lenders offer a fixed-rate conversion option for all or part of the balance, which can provide payment certainty at the cost of some flexibility.

Tax Treatment

The tax deductibility of HELOC interest is narrower than many borrowers assume. Under current IRS guidance, interest on a home equity line is deductible only when the borrowed funds are used to buy, build, or substantially improve the home that secures the loan. Interest on funds used for other purposes, such as paying off credit card debt, funding a vacation, or covering tuition, is generally not deductible. Taxpayers considering a HELOC for deduction purposes should consult IRS Publication 936 or a tax professional, since eligibility depends on the total mortgage debt and how the funds are actually used.

Key Risks to Weigh

• Foreclosure risk: because the HELOC is secured by the home, defaulting can result in the lender initiating foreclosure proceedings, just as with a primary mortgage.
• Rate exposure: variable rates mean monthly payments can increase without warning if the underlying index rises, even absent new borrowing.
• Draw-to-repayment transition: interest-only payments during the draw period can mask the true cost of the loan until amortizing payments begin.
• Credit limit reductions: lenders can freeze or reduce the available credit line if home values fall or the borrower's financial situation changes, a practice the CFPB has documented during past housing downturns.
• Fees: annual fees, early closure fees, and appraisal costs can add to the total expense of opening and maintaining a HELOC.

How It Differs From a Home Equity Loan

A home equity loan provides a fixed lump sum upfront with a fixed interest rate and fixed monthly payments from day one, making it more predictable but less flexible. A HELOC, by contrast, offers flexibility to borrow as needed but introduces variable-rate risk and the two-phase structure described above. Some homeowners use a combination approach, drawing from a HELOC for a renovation project and later converting the balance to a fixed rate once the project is complete, if the lender permits that option.

For homeowners weighing either product, the decision typically comes down to how predictable the borrowing need is, how sensitive the household budget is to rate increases, and whether the funds will be used in a way that could qualify for the mortgage interest deduction. Reviewing the loan estimate and closing disclosure required under federal Truth in Lending Act rules, and comparing at least two or three lenders, remains a practical step before committing to either structure.