Interest on a $200,000 HELOC depends on your rate, how much you actually borrow, and how long you carry the balance
A HELOC (home equity line of credit) is not a fixed loan. You don't borrow $200,000 all at once and pay interest on that full amount for a set term. Instead, you have access to $200,000, and you pay interest only on what you actually draw. The interest rate usually changes with the market, and your payment obligation shifts as you borrow and repay.
This means the interest you pay depends on three things: the interest rate you're offered, how much of that $200,000 you actually use, and how long you carry each balance. A rough example: if your rate is 8% and you borrow $100,000 for one year, you'd pay about $8,000 in interest. If you borrow $200,000 at 8% for one year, you'd pay about $16,000. But most people don't borrow the full amount or carry it for a full year, so actual costs are usually lower.
Key Takeaways
- You pay interest only on the amount you actually draw from the line, not on the full $200,000 credit limit.
- HELOC rates are variable and tied to the prime rate, so your rate and monthly payment can change every month or every quarter depending on your lender's terms.
- Most HELOCs have a draw period (usually 5 to 10 years) when you can borrow and make interest-only payments, then a repayment period (usually 10 to 20 years) when you pay principal and interest.
- The total interest you pay depends on how much you borrow, your rate at the time you borrow, and how long you carry the balance — not on the credit limit itself.
How HELOC interest rates work
HELOC rates are variable, meaning they move with market conditions. Most are tied to the prime rate (the rate banks charge their best customers), plus a margin your lender adds. If the prime rate is 8.5% and your lender's margin is 1%, your rate would be 9.5%. When the prime rate drops, your rate drops. When it rises, so does yours.
This is different from a fixed-rate home equity loan, where your rate stays the same for the entire loan term. With a HELOC, your rate can change monthly or quarterly depending on your lender's terms. That means your monthly payment can go up or down, sometimes significantly. If rates rise sharply, your payment on a $100,000 balance could jump from $750 a month to $900 a month or more.
Your actual rate depends on your credit score, the equity in your home, and current market conditions. Lenders typically offer rates 0.5% to 2% above the prime rate. Right now, rates vary widely by lender and borrower, so you'll need to contact lenders directly for quotes.
Interest during the draw period versus the repayment period
Most HELOCs split into two phases. During the draw period (usually 5 to 10 years), you can borrow and repay as you want, and you typically pay interest only on what you've drawn. Your monthly payment is just the interest owed that month. If you've drawn $50,000 at 8%, your monthly interest payment is about $333.
After the draw period ends, the repayment period begins (usually 10 to 20 years). You can no longer draw new money. Now you must pay both principal and interest on whatever balance remains. If you still owe $100,000, your monthly payment jumps significantly because you're now paying down the loan itself, not just interest.
This shift is important to understand before you open a HELOC. Many people borrow during the draw period, make only interest payments, and then face a payment shock when repayment begins. If you've drawn $150,000 and made only interest payments for 10 years, you still owe the full $150,000 when the repayment period starts, and your payment will roughly double or triple.
A concrete example: $200,000 HELOC at different borrowing levels
The table below shows what you'd pay in interest during a five-year draw period at 8%, assuming you make only interest payments and don't pay down the balance. These are estimates based on a fixed rate; your actual rate will likely change over time.
| Amount Drawn | Interest Rate | Monthly Interest Payment (Draw Period) | Total Interest Over 5 Years (Draw Period Only) |
|---|---|---|---|
| $50,000 | 8% | $333 | $19,980 |
| $100,000 | 8% | $667 | $39,960 |
| $150,000 | 8% | $1,000 | $59,940 |
| $200,000 | 8% | $1,333 | $79,920 |
If rates rise to 10%, your monthly payment on a $100,000 balance would jump to $833, and your five-year interest cost would be about $49,980. If you make principal payments during the draw period, your total interest will be lower because you're reducing the balance subject to interest. The numbers in this table assume you make only the minimum interest-only payment each month.
What happens when the repayment period begins
When your draw period ends and repayment begins, your payment structure changes completely. You're no longer paying interest only. Now you're paying principal and interest, and the payment is calculated to pay off the remaining balance over the repayment period (usually 10 to 20 years).
If you owe $100,000 at the start of repayment and your rate is 8%, a 15-year repayment period would mean a monthly payment of about $955. Over those 15 years, you'd pay roughly $71,900 in total payments, of which about $31,900 is interest. The longer the repayment period, the more total interest you pay, but your monthly payment is lower. A 10-year repayment period would mean higher monthly payments but less total interest paid.
Some lenders allow you to extend the repayment period or convert the remaining balance to a fixed-rate loan. Others require you to pay off the balance in full when the draw period ends. Read your HELOC agreement carefully to understand what happens when the draw period expires, because this transition can be a financial surprise if you're not prepared.
Factors that change how much interest you'll pay
How much you actually borrow: If you open a $200,000 HELOC but only draw $75,000, you pay interest only on $75,000. Many people open a large line for flexibility but use only part of it. The credit limit itself doesn't cost you anything; only the money you actually use does.
How long you carry the balance: If you draw $100,000 and pay it back in six months, you pay far less interest than if you carry it for five years. Interest accrues daily, so the longer the balance sits, the more you owe. Paying down the balance early during the draw period saves you thousands in interest over time.
Rate changes: If rates rise after you open the HELOC, your monthly payment increases. If rates fall, your payment decreases. Over a 10-year draw period, rate swings can add or subtract thousands in interest. This is the biggest variable you can't control, so it's worth planning for the possibility that rates could be higher than they are today.
Whether you make principal payments during the draw period: If you pay down the balance while you're still in the draw period, you reduce the amount subject to interest. Many people pay more than the interest-only minimum to lower their total cost and avoid the payment shock when repayment begins.
How to estimate your own interest cost
To get a rough number for your situation, you need three pieces of information: the interest rate you're offered, the amount you plan to borrow, and how long you plan to carry the balance. Most lenders' websites have HELOC calculators that let you plug in these numbers and see a monthly payment estimate and total interest projection.
Keep in mind that calculators usually assume a fixed rate, but your HELOC rate will change. If you're planning to carry a balance for several years, assume rates could rise 1% to 2% above where they are today, and recalculate. That gives you a more realistic worst-case picture of what you might owe. You can also contact lenders directly and ask for a rate quote based on your credit score and home equity, and they can walk you through their specific draw and repayment terms.
Frequently Asked Questions
Can I pay off a HELOC early without a penalty?
Most HELOCs have no prepayment penalty, so you can pay off the balance at any time without extra fees. Check your agreement to be sure. Paying early reduces the total interest you owe because you're carrying the balance for less time.
What if I only make interest payments during the draw period and then can't afford the repayment period payment?
Contact your lender before the repayment period begins. Some lenders allow you to extend the draw period, convert the balance to a fixed-rate loan, or work out a longer repayment schedule. Waiting until after the period ends leaves you with fewer options and less negotiating power.
Is the interest on a HELOC tax deductible?
HELOC interest may be deductible if you use the borrowed money to improve your home. Interest on money used for other purposes is generally not deductible. Consult a tax professional about your specific situation, as tax rules are complex and change.
Why does my HELOC rate change every month?
Your rate is tied to the prime rate, which moves with Federal Reserve decisions and market conditions. When the prime rate changes, your lender's rate changes automatically. Some lenders adjust monthly, others quarterly. Check your agreement for the adjustment schedule.
What's the difference between a HELOC and a home equity loan?
A home equity loan is a fixed-rate, fixed-payment loan for a set amount. A HELOC is a variable-rate line of credit where you borrow as needed. Home equity loans have predictable payments; HELOCs have flexible borrowing but unpredictable payments that can change with market rates.