HELOC vs Cash-Out Refi for Your Next Down Payment

You own a Seattle-area home with serious equity, and you want to turn some of it into a down payment — for the next house, a rental property, or a buy-before-you-sell maneuver. The two standard tools are a HELOC and a cash-out refinance. They both extract equity. They are otherwise almost opposite products, and choosing the wrong one for your situation can cost real money for years.

Here’s the decision, trade-off by trade-off.

The thirty-second version

• A HELOC (home equity line of credit) is a second loan on top of your existing mortgage — a revolving credit line you draw from when needed and pay interest on only what you’ve drawn. Your current mortgage stays exactly as it is.
• A cash-out refinance replaces your existing mortgage with a new, larger one, and you take the difference in cash. Everything about your old loan — rate, remaining term, payment — is gone; you have a new loan on today’s terms.

That last sentence is doing the heavy lifting. Read it twice.

Trade-off 1: What happens to your existing mortgage rate

This is usually the whole ballgame. If your current mortgage carries a rate lower than what’s available today, a cash-out refi forces you to give it up — on your entire balance, not just the new cash. You’d be repricing hundreds of thousands of dollars of cheap debt to extract a smaller amount of equity. A HELOC, by contrast, leaves the cheap mortgage untouched and prices only the new borrowing.

Flip the scenario and the logic flips: if today’s rates are at or below your existing rate, the cash-out refi stops being expensive and might even improve your base loan while extracting cash.

The rule of thumb: compare the blended cost. Your lender can compute the weighted average rate of (existing mortgage + HELOC) versus the single rate of the cash-out refi, on your actual balances. Whichever blend is cheaper usually wins the math — though not always the risk decision, which is the next section.

Trade-off 2: Fixed certainty vs floating flexibility

HELOC rates are typically variable, floating with the market. Cash-out refis are commonly fixed. So the HELOC’s pricing today is a snapshot, not a promise — if rates climb, your carrying cost climbs with them. For a short-term need (a down payment you’ll repay when your old house sells), the float barely matters. For equity you’ll carry for many years, the float is a genuine bet, and a fixed-rate cash-out (or fixed-rate home equity loan, the HELOC’s fixed cousin) deserves a closer look.

HELOCs also have structural quirks worth knowing: a draw period (years where you can borrow and often pay interest-only) followed by a repayment period (the line freezes and payments rise to amortize the balance). The interest-only years feel cheap; the repayment cliff surprises people who never planned a payoff.

Trade-off 3: Cost and speed to set up

HELOCs are typically cheap and fast to open — closing costs are modest or waived, and the application is lighter. Cash-out refis are full mortgage transactions with full mortgage closing costs. If you might not even use the money (you want optionality while house-hunting), an open-but-undrawn HELOC costs little to nothing to sit there; a cash-out refi makes you pay interest on the full amount from day one whether you’ve found a house or not.

This is why the HELOC is the natural tool for the buy-before-you-sell window — covered in depth in our bridge loan guide and the broader buying-and-selling-at-once playbook.

Trade-off 4: Timing traps

Two sequencing rules that wreck plans when learned late:

1. Open the HELOC before you list. Lenders generally won’t originate a HELOC on a home that’s actively for sale — they don’t want to fund a credit line that gets paid off next month. If a sale is even a maybe, open the line first.
2. Tell your next lender about the draw. Both products affect how you qualify for the next house: the new payment lands in your debt-to-income ratio, and lenders will document where your down payment came from. Borrowed down payments are routine and legitimate — but they must be disclosed and underwritten, never “discovered.” Coordinate both loans with the lender doing your purchase mortgage.

A worked decision, in words

Say you’re keeping your current home as a rental and buying the next primary — a classic Seattle equity move (see single-family vs duplex house hacking for the strategy family). If your existing rate is low, the HELOC almost certainly wins: you preserve the cheap debt on the rental, draw only what the down payment needs, and the rental income helps carry it. If your existing rate is high — maybe you bought recently — price the cash-out refi seriously: you might extract the equity and restructure the base loan in one transaction, with one fixed payment that’s easy to underwrite against rent.

If instead you’re selling the old home within months, the cash-out refi is almost never right — you’d pay full refinance costs for a loan you’re about to extinguish. HELOC, or a true bridge loan if the line can’t be opened in time.

The questions to bring to your lender

• What’s the blended-rate comparison on my actual balances, both directions?
• HELOC: what’s the margin over the index, the draw/repayment structure, and any annual or early-closure fees?
• Cash-out: total closing costs, and the break-even versus the HELOC blend?
• How does each option affect my qualification for the purchase mortgage?
• Any seasoning or listing restrictions I should sequence around?

Then sanity-check the next purchase itself with the affordability calculator and the mortgage calculator — equity extraction tells you where the down payment comes from, not whether the monthly works.

Both products are honest tools. The HELOC is the scalpel: cheap, flexible, floating. The cash-out refi is the full remodel: expensive to set up, fixed, and total. Match the tool to the holding period and to the rate you’d be giving up — and make a lender show you the blended math before you sign either.

While you’re comparing lenders, compare agents the same way. Manaky Homes is a free marketplace where Greater Seattle agents publish their fees and pricing models side by side — join the waitlist to see them when we launch.