Home Equity Loan vs. HELOC: Lump Sum or Revolving Line — and Why Both Put Your House on the Line

Your home appraised for $120,000 more than you owe on it, and the contractor just quoted $55,000 for the addition you have been planning for two years. The equity is sitting there, and two different lenders have already offered to turn it into cash — one as a single check with a fixed monthly payment, the other as a credit line you can draw on whenever you like. They sound like flavors of the same thing, but they behave nothing alike once the money starts moving: one punishes you for borrowing too much up front, the other punishes you for borrowing too casually over time, and choosing by interest rate alone is how people end up with a payment that doubles a decade from now.

A home equity loan hands you a lump sum at closing and you repay it in fixed installments, like a second mortgage. A home equity line of credit — a HELOC — gives you a revolving credit limit you draw against as needed during a multi-year draw period, usually with a variable rate and interest-only minimum payments, followed by a repayment period when the line closes and the balance amortizes. Both are secured by your home, which is what makes their rates cheaper than unsecured borrowing and what makes the downside serious. This guide walks through how each one works, where the real costs hide, how much you can actually borrow, what the tax rules allow, and how to track either one cleanly in your books.

Lump Sum vs. Revolving Line: The Core Difference​

The single most important distinction is when you receive the money and when interest starts running.

With a home equity loan, the full amount lands in your account at closing and interest starts accruing on all of it immediately. Borrow $55,000 and every dollar of it is working against you from day one, whether you spend it this month or next year. In exchange you get certainty: a fixed rate, a fixed monthly payment, and a fixed payoff date, typically 5 to 30 years out.

With a HELOC, you get a credit limit — say $80,000 — and draw only what you need, when you need it. Draw $20,000 for the foundation work and you pay interest on $20,000, not $80,000. Repay it and the credit becomes available again, like a credit card. The trade is flexibility for predictability: the rate is usually variable, the payment moves with it, and the loan has two distinct life phases with very different payment behavior.

Neither structure is better in the abstract. A lump sum is cheaper and simpler when you know the number; a line is cheaper and safer when you do not, because you never pay interest on money you have not spent yet.

How a Home Equity Loan Works​

Think of it as a second mortgage that sits behind your first one. The lender orders an appraisal, underwrites your income and credit, and at closing wires you the full amount. From the first month you pay principal plus interest on a fixed schedule, and the balance declines steadily to zero.

Because the loan is a known amount on a known schedule, everything about it is quotable up front: the rate, the payment, the total interest over the life of the loan, and the closing costs. Closing costs on a home equity loan typically run 2 to 5 percent of the loan amount — appraisal fee, origination fee, title search and insurance, recording fees — much like a smaller version of a mortgage closing. On a $55,000 loan, expect roughly $1,100 to $2,750 at the table, though some lenders offer no-closing-cost options that fold the costs into a slightly higher rate.

The discipline is built in. Once the balance is paid down, that credit is gone — you cannot redraw it without applying for a new loan. That rigidity is a feature when the temptation to keep borrowing is the risk: the loan forces an end date on the debt.

The weakness is over-borrowing. Because you must name the amount up front, borrowers routinely pad the request "just in case" — and then pay years of interest on the padding. If the addition ends up costing $48,000 instead of $55,000, the extra $7,000 still accrues interest from closing day until you pay it off.

How a HELOC Works: Draw Period, Then Repayment Period​

A HELOC has two phases, and misunderstanding the handoff between them is the most expensive mistake in this entire topic.

The draw period typically lasts 5 to 10 years. During it, you can borrow up to your credit limit, repay, and borrow again. Most HELOCs require only interest payments on the outstanding balance during this phase, which keeps the minimum payment low while you are actively using the line. Draw $30,000 at 8 percent and your minimum payment is about $200 a month — comfortable enough that it is easy to forget the principal is not shrinking at all.

The repayment period typically lasts 10 to 20 years. When the draw period ends, the line closes to new borrowing and whatever you still owe converts into an amortizing loan: principal plus interest, every month, until it is gone. That same $30,000 balance, amortized over 15 years at 8 percent, costs about $287 a month — and if rates rose during the draw period, the payment is higher still. Borrowers who spent a decade making interest-only minimums experience this as a sudden near-doubling of the payment. Some HELOCs are worse: instead of amortizing, they demand a balloon payment of the entire remaining balance when the draw period ends, forcing you to refinance, sell, or scramble.

A few more mechanics worth knowing before you sign:

• The rate floats. Most HELOCs charge prime plus a margin the lender sets from your credit profile — prime plus 0.5 percent for strong borrowers, prime plus 2 percent or more for weaker ones. When the Federal Reserve moves, your payment moves, usually within a billing cycle or two.
• Caps and floors bound the damage. Federal rules and most contracts cap how far the rate can rise — a common structure limits increases to 2 percentage points per year with a lifetime ceiling around 18 percent — and many HELOCs also have a floor the rate cannot fall below. Ask for all three numbers in writing.
• Access has friction by design. Many HELOCs set minimum draw amounts (often $300 to $500 per advance) and some charge a transaction fee per draw, an annual maintenance fee of $50 to $100, or an inactivity fee if you never use the line. None of these are large, but they are the reason a HELOC you open "just in case" still costs something.
• Some lenders offer a fixed-rate lock. A common feature lets you convert part of your drawn balance to a fixed rate and fixed payment for a set term, while the rest of the line keeps floating. If your lender offers it, that option is worth real money when rates are rising.

Fixed vs. Variable: Who Carries the Rate Risk​

With a home equity loan at a fixed 8 percent, the lender has made a bet that rates will not rise far above 8 percent for the life of your loan — and if they do, you keep your 8 percent and the lender eats the difference. With a HELOC at prime plus 1 percent, you carry that risk instead. When borrowing costs climbed steeply in 2022 and 2023, fixed-rate borrowers noticed nothing while HELOC minimum payments rose month after month on balances that were not shrinking.

That does not make variable rates a bad deal. HELOC starting rates are often lower than home equity loan rates precisely because the borrower absorbs the rate risk, and if rates fall you benefit automatically without refinancing. The honest question is about your cash flow, not your rate forecast: if your HELOC payment rose 40 percent over two years while the balance stayed flat, would you still be comfortable? If the answer is no, the fixed loan's higher starting rate is buying insurance you actually need.

Run the payment-shock math before you sign. Take the maximum you might plausibly have drawn by the end of the draw period, amortize it over the repayment period at the lifetime cap rate — not the introductory rate — and compare that payment to your budget. If the worst case fits, the HELOC's flexibility is genuinely affordable. If it does not, you are betting your house payment on rates staying friendly for a decade.

What Each One Costs to Open​

Home equity loans look like small mortgages at closing: appraisal ($300 to $700), origination fee (up to 1 percent of the loan), title and recording fees, and sometimes discount points. The 2-to-5-percent rule of thumb holds, which means closing costs can exceed a full year of interest savings on a small loan — always divide the closing costs by the monthly savings versus your next-best option to see how many months it takes to break even.

HELOCs are usually cheaper to open. Many lenders charge little or nothing at origination — no application fee, no closing costs, sometimes even covering the appraisal — because the line costs them little until you draw. The costs instead arrive over time and at exit: annual fees during the draw period, per-draw minimums, and early-termination or prepayment fees (commonly a few hundred dollars, sometimes the reimbursement of waived closing costs) if you close the line within two to three years of opening it.

Neither cost structure dominates. A $15,000 project favors the HELOC's near-zero opening costs; a $100,000 project amortizes the home equity loan's closing costs quickly while the fixed rate does its work.

How Much You Can Borrow: The CLTV Ceiling​

Lenders limit total borrowing against your home with the combined loan-to-value ratio — CLTV. Add up everything secured by the home (your first mortgage balance plus the new loan or line) and divide by the appraised value. Most lenders cap CLTV at 80 percent; some stretch to 85 or 90 percent for strong borrowers, usually at a higher rate.

The arithmetic decides your real budget. On a $400,000 home with a $280,000 mortgage balance and an 80 percent cap, total secured debt cannot exceed $320,000 — so the maximum new borrowing is $40,000, not the $120,000 of headline equity. Borrowers consistently overestimate what is available because they compute equity (value minus mortgage) and forget the lender keeps a 20 percent cushion above that.

Beyond equity, underwriting looks like a mortgage application: credit score (620 is a common floor, with the best terms reserved for 700-plus), debt-to-income ratio (usually capped around 43 to 50 percent including the new payment), stable income, and a clean appraisal. Apply with the same preparation you would bring to a refinance, because the lender is taking the same collateral.

The Tax Rules: Deductible Only When the Money Improves the House​

Interest on a home equity loan or HELOC is deductible only when the proceeds buy, build, or substantially improve the home that secures the loan — the IRS calls qualifying borrowing "acquisition debt." Remodel the kitchen, add the bedroom, replace the roof: the interest generally qualifies. Use the same loan to pay off credit cards, buy a car, cover tuition, or fund a vacation: the interest is not deductible, even though your house secures the debt. The loan type is irrelevant; only the use of the money matters.

Three details catch people:

• The debt ceiling is shared. Deductible mortgage interest applies to total acquisition debt up to $750,000 ($375,000 if married filing separately) for loans taken out after December 15, 2017. Your first mortgage and the home equity borrowing count together against that limit.
• Mixed uses split the interest. Draw $40,000 from a HELOC and spend $25,000 on the addition and $15,000 on a car, and only the interest attributable to the $25,000 is deductible. Interest-tracing rules allocate each dollar of interest to the use of the dollar that generated it — which is a strong argument for keeping improvement draws and personal draws in separate, documented transfers rather than commingling them.
• Records win audits. Keep the closing disclosure, every draw record, contractor invoices, and proof the spending improved the secured home. Deductibility is a facts-and-circumstances claim you substantiate, not a box the lender checks for you — the Form 1098 reports how much interest you paid, not whether it qualifies.

Tax law also interacts with the standard deduction: with a high standard deduction, many borrowers take it instead of itemizing, in which case the mortgage-interest deduction has no value at all that year. Know whether you itemize before you treat deductibility as a deciding factor.

When Each One Wins​

Match the tool to the shape of the spending:

Take the home equity loan when the price is known and final. A signed $55,000 construction contract, a $20,000 tuition bill, a defined debt-consolidation payoff amount. The fixed payment lets you budget to the dollar, and the forced amortization means the debt actually ends. It also wins for one specific behavioral reason: consolidating credit card debt with a lump-sum loan works only if the cards stay paid off, and a loan that cannot be redrawn cannot become the second half of a debt spiral.

Take the HELOC when spending is phased, uncertain, or spread over years. A multi-stage renovation where each phase is quoted separately, college costs arriving semester by semester, a business owner smoothing seasonal gaps. Drawing in stages means you pay interest only on deployed money, and the revolving feature covers the "while we are at it" discoveries every renovation produces. It also serves as a standby facility: an open, undrawn line costs little per year and beats liquidating investments or missing payroll when a surprise arrives.

Think twice about both when the spending is consumption. Financing a vacation, a wedding, or depreciating purchases against the roof over your head converts unsecured lifestyle spending into foreclosure risk. The rate looks attractive next to a credit card, but the collateral changes the stakes completely — a missed credit card payment damages your score, while a missed home equity payment can start the process that takes the house.

The Risk Both Share: Your House Secures the Debt​

Strip away the structural differences and one fact remains: default on either loan and the lender can foreclose. A second lienholder forecloses subject to the first mortgage — the first lender gets paid first from the sale — but "second in line" is cold comfort when the outcome is losing the home. Borrow an amount whose worst-case payment you can make from ordinary income in a bad year, not a good one, and never secure borrowing you could not survive being called.

Two HELOC-specific risks deserve their own warnings. First, the lender can generally freeze new draws or reduce your credit limit if your home's value falls significantly or your financial condition deteriorates — which tends to happen exactly when you need the line most, since job loss and falling prices arrive together. A HELOC is a fair-weather facility; do not count it as your emergency fund. Second, the revolving structure quietly enables permanent debt: borrowers who make interest-only minimums for a decade, then roll the balance into a new HELOC at the next bank, convert a temporary bridge into a lifelong interest stream. If your balance is not lower than it was two years ago, the line owns you, not the reverse.

Tracking Either Loan in Your Books​

Home equity borrowing generates exactly the kind of mixed, multi-year money trail that becomes a mess without deliberate bookkeeping: draws landing in checking alongside income, interest partly deductible and partly not, improvement spending that raises your cost basis at sale. Set up the accounts before the first draw and every tax season afterward is a report, not an excavation.

Keep the loan itself in a dedicated liability account, separate from your mortgage, and route every draw through it so the balance always reconciles to the lender statement. Split interest explicitly: deductible acquisition-debt interest in one expense account, nondeductible personal interest in another. And capitalize improvement spending against the property rather than expensing it — those dollars raise your basis and reduce taxable gain when you sell. In plain-text books the structure looks like this:

2026-03-15 open Liabilities:HomeEquity:HELOC USD
2026-03-15 open Expenses:Interest:Deductible:HomeEquity USD
2026-03-15 open Expenses:Interest:Nondeductible:HomeEquity USD
2026-03-15 open Assets:Property:HomeImprovements USD
 
2026-04-02 * "HELOC draw #1 -- kitchen remodel deposit" "Lender-1234"
  Assets:Cash:Checking          25000.00 USD
  Liabilities:HomeEquity:HELOC -25000.00 USD
 
2026-04-10 * "Pay contractor -- kitchen remodel" "Invoice-88"
  Assets:Property:HomeImprovements  25000.00 USD
  Assets:Cash:Checking             -25000.00 USD
 
2026-05-01 * "HELOC interest -- April, improvement use" "Lender-1234"
  Expenses:Interest:Deductible:HomeEquity   166.67 USD
  Assets:Cash:Checking                     -166.67 USD

Each draw gets its own dated transaction with a memo naming the use, so interest tracing is mechanical: improvement draws point at deductible interest, personal draws at nondeductible interest. If you keep your ledger in Beancount, the documentation covers balance assertions that catch a missed payment the day it happens, and watching the liability balance shrink month by month in Fava is the fastest feedback loop there is for staying ahead of the repayment-period reset.

Choosing: Questions to Ask Before You Sign​

Narrow it to one page of homework. Get written answers to these from every lender you compare:

1. What is the rate, and is it fixed or variable? If variable, what index and margin set it, and what are the periodic cap, lifetime cap, and floor?
2. For a HELOC: how long is the draw period, what is the minimum payment during it, and exactly what happens to the balance when it ends — amortization over how many years, or a balloon?
3. What are the total closing costs, and which fees recur — annual fee, per-draw fee, inactivity fee, early-termination fee?
4. What is the CLTV ceiling, the minimum draw, and the minimum credit line the lender will open?
5. Can a HELOC balance be locked to a fixed rate, in whole or in part, and what does each lock cost?
6. What is the worst-case monthly payment — maximum plausible balance, amortized over the repayment period at the lifetime cap — and does it fit a bad-year budget?

Then match the answer sheet to your spending: known lump sum, take the loan; phased or uncertain draws, take the line; consumption you could not pay cash for, take neither. Get the structure that fits the job, set up the tracking before the first dollar moves, and the equity you spent a decade building will still be working for you — instead of against you — when the last payment clears.