When homeowners want to tap equity to pay off their mortgage faster, two tools dominate the conversation: a home equity line of credit (HELOC) and a cash-out refinance. The short answer is that a HELOC works best for disciplined borrowers using the velocity banking method on a smaller balance, while a cash-out refinance makes sense only when current rates are meaningfully lower than your existing mortgage rate. Choosing wrong can add tens of thousands in interest instead of saving it.
Below, we'll break down how each option works, run the real numbers on a $320,000 mortgage at 6.5%, and show you exactly when each strategy accelerates your payoff versus when it backfires.
What Is a HELOC vs. Cash-Out Refinance and How Does Each Work?
A HELOC is a revolving line of credit secured by your home's equity. You're approved for a maximum credit limit (typically up to 85% of your home's value minus what you owe), and you can draw, repay, and redraw funds during a 5-10 year draw period. HELOCs usually have variable interest rates tied to the prime rate, and you only pay interest on what you actually borrow.
A cash-out refinance replaces your existing mortgage with a new, larger loan. The difference between the new loan amount and your old balance comes to you as cash at closing. You're effectively starting over with a brand-new 15- or 30-year fixed mortgage, often at a different interest rate.
Here's a concrete example. Say you owe $320,000 on a 30-year mortgage at 6.5%, and your home is worth $500,000. You have $180,000 in equity. Lenders typically allow you to borrow up to 85% of your home's value combined ($425,000), meaning you could access roughly $105,000 in either product.
The math formula in plain English: Maximum borrowing = (Home value × 0.85) − Current mortgage balance. So ($500,000 × 0.85) − $320,000 = $105,000 of available equity.
For early payoff strategies, the HELOC is typically used in a method called velocity banking, where you draw a chunk (say $25,000), throw it directly at your mortgage principal, then aggressively repay the HELOC using your monthly cash flow before drawing again. The cash-out refinance approach is different: you'd refinance into a shorter term (like 15 years) to force a faster payoff with a lower rate.
How Much Can You Actually Save?
Let's compare scenarios for our $320,000 loan at 6.5% with 30 years remaining (monthly payment of $2,022 principal and interest). The standard payoff results in $407,925 of total interest over 30 years. Now look at how three different acceleration strategies stack up:
| Strategy | Monthly Payment | Total Interest | Payoff Date | You Save |
|---|---|---|---|---|
| Standard 30-year | $2,022 | $407,925 | Year 30 | $0 (baseline) |
| +$100 extra/month | $2,122 | $348,640 | Year 26.5 | $59,285 |
| +$250 extra/month | $2,272 | $282,940 | Year 22.4 | $124,985 |
| +$500 extra/month | $2,522 | $217,860 | Year 18.2 | $190,065 |
| HELOC velocity (draw $25K) | $2,022 + HELOC repay | ~$255,000 | Year 20-22 | ~$150,000 |
| Cash-out refi to 15-yr at 6.0% | $2,700 | $166,000 | Year 15 | $241,925 |
The cash-out refinance to a 15-year term shows the largest interest savings, but it requires a much higher monthly payment ($2,700 vs. $2,022) and only works if you can secure a lower rate. To run your own numbers with different scenarios, try our extra payment calculator to see exactly how additional principal payments affect your timeline.
Step-by-Step: How to Choose Between a HELOC and Cash-Out Refinance
- Pull your current mortgage statement and calculate your equity. You need to know your exact balance, interest rate, remaining term, and current home value (use Zillow or a free appraisal as a starting point). Without these four numbers, you can't make a smart comparison.
- Get rate quotes for both products on the same day. Contact at least three lenders for HELOC quotes and three for refinance quotes. Rates can vary by 0.5-1.0%, which translates to thousands over the life of the loan.
- Calculate total cost, not just monthly payment. Cash-out refinances typically charge 2-5% in closing costs ($6,000-$15,000 on a $300,000 loan), while HELOCs often have minimal or no closing costs. Factor these into your break-even analysis.
- Stress-test the HELOC for rising rates. Most HELOCs are variable-rate. Calculate your payment if rates rose 2-3% to make sure you can still afford the strategy. If a rate spike would derail you, choose the fixed-rate refinance instead.
- Build a written payoff plan with specific dates. Use our amortization schedule tool to map out exactly when each principal reduction happens. Print it and check progress monthly.
- Set up automatic transfers immediately. Whether you're making extra principal payments or repaying a HELOC draw, automation removes the temptation to skip a month. Schedule transfers for the day after payday.
- Review your strategy annually. Interest rates, home values, and your income change. Revisit your plan each January to adjust extra payments upward or refinance again if rates drop significantly.
Common Mistakes Homeowners Make with HELOCs and Cash-Out Refinances
- Refinancing into a longer term. Going from a 30-year mortgage with 22 years left into a fresh 30-year refi resets the clock. Even at a lower rate, you may pay more total interest. Always refinance into an equal or shorter term to actually save money.
- Using a HELOC without discipline. Velocity banking only works if you aggressively repay the draw within 12-24 months. Homeowners who treat the HELOC like a credit card end up paying interest on both their mortgage and the line of credit, often increasing total debt.
- Ignoring closing costs in the math. A cash-out refinance saving 0.5% on rate may not break even for 5-7 years after closing costs. If you're planning to move within that window, the math doesn't work.
- Forgetting the tax implications. Interest on HELOCs and cash-out refinances is only tax-deductible if used for home improvements (under current IRS rules). Using either to pay off your existing mortgage doesn't qualify for the deduction in most cases.
Is a HELOC or Cash-Out Refinance Right for You? Key Questions to Ask
Is your current mortgage rate higher than today's market rate by 0.75% or more? If yes, a cash-out refinance into a 15- or 20-year fixed could save significantly. If no, refinancing likely costs more than it saves once you factor in closing costs.
Do you have stable, predictable income that can absorb a higher payment? A 15-year refi requires a 25-35% higher monthly payment. If your income varies (commission, self-employed, seasonal), the flexibility of extra payments or a HELOC may be safer than a locked-in higher payment.
Can you commit to repaying a HELOC draw within 24 months? Velocity banking only works with rapid repayment. If your monthly cash surplus is less than $1,500, the math rarely works out — you're better off making direct extra principal payments or trying biweekly payment splits.
Will you stay in the home at least 5 more years? Cash-out refinance closing costs require time to recoup. If you might sell within 5 years, the HELOC's lower upfront costs make it the smarter choice.
Frequently Asked Questions
Can I use a HELOC to pay off my entire mortgage at once?
Technically yes if you have enough equity, but it's rarely smart. HELOCs have variable rates that could spike, and you'd be replacing fixed-rate debt with variable-rate debt. The strategy only makes sense if you can repay the HELOC within 2-3 years.
Which has lower closing costs, a HELOC or cash-out refinance?
HELOCs typically have minimal closing costs ($0-$500), while cash-out refinances run 2-5% of the loan amount, often $6,000-$15,000. This cost difference is the single biggest reason HELOCs win for short-term strategies.
Will a cash-out refinance hurt my credit score?
You'll see a temporary 5-15 point dip from the hard inquiry and new account. Within 6-12 months, scores typically recover or improve as you make on-time payments. The impact is similar for opening a HELOC.
Can I deduct the interest on a HELOC used to pay off my mortgage?
Generally no. Under current IRS rules (post-2017 tax reform), HELOC and home equity loan interest is only deductible if the funds are used to buy, build, or substantially improve your home. Using it to pay down existing mortgage debt doesn't qualify.
What credit score do I need for the best rates on either product?
For top-tier rates on a cash-out refinance, you'll want a 740+ FICO score. HELOCs are slightly more flexible — many lenders offer their best rates at 720+. Below 680, expect rates 1-2% higher than advertised, which often eliminates the savings.
The bottom line: a cash-out refinance wins when current rates are at least 0.75% below your existing rate and you're committed to a shorter term. A HELOC wins for disciplined borrowers using velocity banking on a manageable balance. For most homeowners, simply making consistent extra principal payments delivers 80% of the benefit with none of the complexity. Run your own numbers with our free extra payment calculator to see exactly how much you can save before committing to either strategy.