Buy Before You Sell in Austin (2026): Bridge Loans, Texas HELOC Rules, and Keeping Your 3% Mortgage

The hardest house to buy in Austin right now is the one you want while you still own the one you have. Roughly half of American homeowners with a mortgage carry a rate at or below 4%, the 30-year fixed sat at 7.40% in Freddie Mac's survey the week of October 15, and the Fed meets this week with futures pricing another hike by December, not a cut. Every month you keep the old loan you save money; every month you wait for it to sell you risk losing the next house. That tension has a name in underwriting: the departing residence. This guide covers the five ways to buy before you sell in Austin, what each one costs in 2026 dollars, the Texas rules that make two of them different here than anywhere else, and a new Fannie Mae rule that lands December 1 and changes the math on keeping the old house as a rental.

In this guide

• Why this is a 2026 question
• Austin in October 2026: the market that makes this possible
• The five ways to buy before you sell in Austin
• Path 1: sell first, and make the gap short
• Path 2: the contingent offer is back
• Path 3: bridge loans and the buy-before-you-sell programs
• Path 4: the Texas HELOC, the state's best-kept move-up tool
• Path 5: keep the old house, and the Fannie Mae rule that changes December 1
• The worked example: $1.2M Allandale to $2.2M Westlake
• After the sale: recast, don't refinance
• The 150-day sequence
• Eight mistakes we see
• When each path wins
• How Echelon runs this
• Frequently asked questions

Why this is a 2026 question

Three numbers explain why move-up buyers are stuck.

The people who do move anyway are the ones who have to: a third child, a parent moving in, a job that landed on the other side of MoPac. For them the question is not whether to give up the 3% loan. It is how to control the gap between two closings without paying for it twice.

Austin in October 2026: the market that makes this possible

The same market that makes selling slow makes buying forgiving. Unlock MLS's September 2026 Central Texas Housing Report (released October 13) and the weekly Austin-area MLS counts show a two-speed market: central Austin firming, the suburbs loosening, and the luxury tier sitting on inventory.

*Sources: Unlock MLS September 2026 report as summarized by Compass/Serendipity (Oct 19, 2026); Team Price weekly market update (Oct 15, 2026). Redfin counted 17,972 sellers against 8,360 buyers in metro Austin in August, which put Austin in its top 10 buyer's markets nationally (CultureMap, Sept 17, 2026).*

Two things in that table matter for a buy-before-you-sell plan.

First, sellers are negotiating. A 97.2% average sale-to-list is after price cuts; measured against original list price, our Unlock MLS trailing-12-month work has the combined discount in the city near 7%, and only about 61% of listings that go live actually close (the rest expire or withdraw). See how long it takes to sell a house in Austin and why luxury homes don't sell in Austin for the tier-by-tier version. A seller who has watched 140 days tick by is a seller who will take a contingent offer or a 45-day close.

Second, the luxury tier is slow but liquid. The Reisor Team's weekly count of $2 million-plus contracts in Austin and West Lake Hills ran at nine contracts a week in mid-October, about $30 million in volume, with single-family contracts averaging 141 days on market and $740 per square foot (The Real Deal, Oct 21, 2026). Nine a week is a market where the house you want will still be there in 60 days. It is also a market where your $1.2 million house in a central neighborhood, priced to the market, moves faster than the $2.2 million one you are buying: Team Price's weekly data has recent listings that are priced correctly going under contract in a median of 7 days.

Fast house, slow house: 78757 vs 78746

The worked example later in this post sells in 78757 and buys in 78746. These are the trailing-12-month numbers behind the strategy.

*ZIP columns are the Agent Intel housing dataset (all residential segments) behind our Austin home prices by ZIP code hub; the city column is Unlock MLS trailing-12 data to September 30, 2026. Unlock MLS's own 78746 figures tell the slow-house story in more detail: 319 closings, a 56.9% listing success rate (248 listings expired or were withdrawn), 245 price reductions, a median of 48.5 days to contract but an average of 90.2 because of the stale tail, and a combined discount from original ask of about 8.5%.*

Read the two ZIP columns as a seller and a buyer. In 78757 you are selling a house 25 days faster than the one you are buying, into a ZIP where prices rose 6.9% and sellers still get 96.7% of their last ask. In 78746 you are buying from a seller whose neighborhood carries 5.3 months of supply, where 43% of listings never close with their first agent, and where the average listing has sat three months. Both columns favor the same plan.

That asymmetry is the whole strategy. Buy the slow house first, on your timeline. Sell the fast house second, vacant and staged, without a kitchen full of moving boxes in the listing photos.

The five ways to buy before you sell in Austin

There are five structures. Everything else is a brand name for one of them.

The last row is the trick. A contingent buyer who has a HELOC or bridge approval in a drawer can waive the contingency the day the kick-out notice arrives. A contingent buyer without one is bluffing, and listing agents know it.

Path 3: bridge loans and the buy-before-you-sell programs

A bridge loan is six to twelve months of interest-only money secured by the house you are leaving, used to fund the down payment on the one you are buying, repaid when the old house closes. The 2026 market has three flavors.

Bank and private-bank bridge loans. Texas banks and the private banks that serve $2 million-plus buyers write bridge loans at roughly 9% to 11% interest-only, one to two points, and a 6- to 12-month term, usually cross-collateralized against both properties. Expect a full underwrite of both payments. On a $440,000 bridge over four months: about $14,700 in interest at 10%, $6,600 in points, and $1,500 in closing costs, around $22,800 all-in.

Buy-before-you-sell platforms. Two of the largest are headquartered in Austin: Homeward (founded in 2018 by an Austin agent) and Calque, the trade-in-mortgage company that partners with lenders. Knock (bridge loan), Orchard (equity advance, must list with an Orchard agent) and HomeLight (equity unlock) also operate here. They sell the same thing with different wrappers: a down-payment advance, a contingency-free offer, and a backup offer on your old house (typically 80% to 85% of value) if it does not sell inside the program clock.

*Fee schedules are the companies' published 2026 figures and change without notice; confirm them in writing. The backup offer is the part to read twice. At 82% of a $1.2 million value, the backstop is a $216,000 haircut; it is insurance, not a plan.*

Path 4: the Texas HELOC, the state's best-kept move-up tool

Texas regulates home-equity lending in its constitution, which is why most national "buy before you sell" advice is wrong here. Article XVI, Section 50(a)(6) and 50(t) set the rules for a second lien on your homestead:

*Sources: Texas Constitution Art. XVI §50; Texas Finance Commission 7 TAC Chapter 153 (2018 amendments); lender summaries linked in Sources.*

The sequencing is the whole game. Lenders will not open a HELOC on a house that is listed, and most want it unlisted for 90 to 180 days. So the order is: apply for the line, wait the 12 days, close, wait the 3-day rescission, then list. The draw is interest-only during the draw period at prime plus a margin; prime is 7.00% after the Fed's September hike, and Bankrate's national average for a $30,000 HELOC was 7.47% in June, so budget 7.5% to 8.25% for a strong-credit borrower in Q4 2026. Interest on $249,000 for four months at 7.75% is about $6,430.

Two more points that matter in Texas:

• Do not cash-out refinance. A cash-out refinance is also a §50(a)(6) loan, and it replaces your 3% first lien with a 7.4% one. The HELOC leaves the first lien untouched; the old loan keeps running at 3% until the sale pays it off.

• Borrowed down payment is allowed. Fannie Mae, Freddie Mac and most jumbo investors accept funds borrowed against real estate you own as a down-payment source; the HELOC payment just has to fit in your debt-to-income ratio. Disclose it on the application. Undisclosed liens surface at closing on the title commitment.

Path 5: keep the old house, and the Fannie Mae rule that changes December 1

The "accidental landlord" path is the one most people assume they will take and the one that pencils least often. Fannie Mae's Selling Guide Announcement SEL-2026-08 (September 2, 2026, updated September 23) rewrote the departing-residence rules; lenders may use them now and must for applications dated December 1, 2026 or later (Fannie pushed the date back from November 1).

The practical effect: the friend-of-a-friend lease at an optimistic number is gone. Your lender will run an appraiser's market-rent figure (a $1.2 million central Austin house rents for roughly $4,500 to $5,000 a month in late 2026), take 75% of it, and subtract the house's full payment. For the worked example that is $3,600 against a $5,375 PITIA: a $1,775 monthly shortfall that goes straight into your debt-to-income ratio on the new jumbo, plus $32,250 in extra reserves. The numbers still work for a lot of high-income buyers; they no longer work on paper alone.

Three Texas-specific costs of keeping the house, covered in depth in sell or rent my house in Austin:

1. 01
   The homestead exemption leaves with you. On a $1.2 million house the lost exemptions add roughly $4,000 to $4,500 a year in property tax at 2025-2026 rates, and the 10% appraisal cap goes with it (non-homestead property gets the 20% circuit breaker through December 31, 2026). Details in Texas homestead exemption 2026.

1. 01
   The Section 121 clock starts. You keep the $500,000 married gain exclusion only if you sell within three years of moving out (two of the last five years as a primary residence). See capital gains tax on a home sale in Texas.

1. 01
   The yield. At $4,800 rent, $24,800 in taxes without the exemption, $3,600 insurance, $6,000 maintenance and 5% vacancy, the house throws off about $20,300 a year: a 1.7% cap rate on $1.2 million. The 3% mortgage is the only reason it is not a bad rental, and it is a good enough reason for some owners. Your lender does not care either way; the rate does not change when a tenant moves in, and renting after the 12-month occupancy period on a primary-residence loan does not trigger the due-on-sale clause.

The worked example: $1.2M Allandale to $2.2M Westlake

The setup

A couple bought a $1 million house in Allandale (78757) in mid-2021 with 20% down and an $800,000 loan at 3.00%. Five years in, the house is worth $1.2 million and the balance is about $711,000. They are buying a $2.2 million house in Westlake (78746, Eanes ISD) with 20% down on a 30-year jumbo. Jumbo pricing has run a bit under the conforming average all year, so the example uses 7.25% against Freddie Mac's 7.40% conforming rate.

Selling costs follow what it costs to sell a house in Austin. The $440,000 down payment is the problem: $411,000 of it is sitting in the Allandale house until that house closes.

The double-carry clock

The new PITI gets paid in every scenario; the overlap cost is the old house's $5,375 a month, plus whatever the gap financing costs. Measure it against a price cut, because that is the real alternative.

That table is why a vacant, staged house priced 2% under the number you wanted is usually the cheap option. In the citywide trailing-12 data, roughly 39% of Austin listings never close with the agent that listed them, and nearly all of those started high. See how to price a luxury home in Austin and the best time to sell a house in Austin for the seasonal version (listing a central Austin house in early November beats listing it in October, and both beat December).

Five paths, 120 days of overlap, all-in cost

A refinance would cost $10,000 to $20,000 in closing costs for the same rate; save it for the day rates are actually lower. Two caveats: FHA and VA loans generally cannot be recast, and some jumbo investors will not. Ask the question before you sign the new loan, not after.

The 150-day sequence

The order matters more than the product. This is the sequence we run for a HELOC-funded, non-contingent purchase; swap a bridge loan into step 3 if the house is already listed.

1. 01
   Day -60: underwrite both payments. Get a fully underwritten approval on the new purchase that already includes the departing residence. If you intend to keep the old house, ask the lender whether it has adopted SEL-2026-08 early; after December 1 every conventional file uses market rent and the six-month reserve rule.

1. 01
   Day -50: order the appraisal with a rent schedule. One appraisal with a Form 1007 rent addendum serves the HELOC lender and, if you keep the house, the Fannie Mae departing-residence calculation.

1. 01
   Day -45: apply for the HELOC. The 12-day waiting period starts when the lender delivers the consumer-rights notice. Do not list the house. Do not put a sign in the yard. Do not post it as coming soon.

1. 01
   Day -30: close the HELOC, wait the 3-day rescission. Funds are available around day -26. Draw nothing yet.

1. 01
   Day -25: write the offer. Non-contingent, or contingent with a 45-day deadline and a kick-out you can waive because step 4 is done. Target listings past 60 days; ask for a 45-day close.

1. 01
   Day 0: close the new house. Draw the HELOC at the title company for the down payment; wire the balance from savings. File the homestead exemption on the new house (Texas prorates it in the year of purchase; your old homestead stays in place through December 31).

1. 01
   Day +7 to +14: move, stage, list the old house. Vacant, photographed empty of your life, priced to the market rather than to your 2022 memory of it. See best time to sell a house in Austin for the month-by-month calendar.

1. 01
   Day +45: under contract. A correctly priced central Austin house is going under contract in days; a luxury one in months. Price for the former.

1. 01
   Day +90 to +120: close the old house. The title company pays off the 3% first lien and the HELOC in the same disbursement.

1. 01
   Day +130: recast the jumbo. Send the servicer the lump sum and the recast request; the new payment shows up on the next statement.

Eight mistakes we see

1. 01
   Listing before the HELOC funds. The line dies the moment the MLS status flips. Sequence it or lose it.

1. 01
   Cash-out refinancing the 3% loan. It is the same §50(a)(6) lien with a 7.4% rate attached. The HELOC leaves the first lien alone.

1. 01
   Forgetting the 12-month rule. A cash-out refi or HELOC closed in the last year blocks a new one until that anniversary.

1. 01
   Planning on a lease after December 1. Fannie Mae's departing-residence rule no longer accepts one. Budget on 75% of an appraiser's market rent and six months of reserves.

1. 01
   Letting the program clock run out. Knock's 6 months and Orchard's 120 days end in a backup offer at 80% to 85% of value. Price to sell inside the clock.

1. 01
   Buying with 10% down to shrink the gap. On a $2.2 million purchase that usually means a jumbo second lien or PMI at a rate that eats the HELOC savings twice over.

1. 01
   Two homestead exemptions. Texas allows one. Claim the new house, and expect the old house's tax bill to reset if you keep it.

1. 01
   Not asking about recast before signing. It is a two-sentence question that is worth $1,100 to $2,700 a month in the example above.

When each path wins

How Echelon runs this

Most of the move-up purchases we close above $2 million never carried a bridge loan, because the purchase was negotiated off-market with a closing date that fit the sale, or because the HELOC was opened 45 days before the client ever saw the house. The sale side gets listed vacant, priced from a current CMA rather than a 2022 Zestimate, and timed to the Austin seasonal calendar. If you are weighing the next house while you still own this one, send us both addresses. We will run the five-path table on your actual numbers, including the December 1 departing-residence math, before you talk to a lender.

Send us both addresses

We'll run the five-path table on your actual numbers, including the December 1 departing-residence math, before you talk to a lender. Talk to Taylor or call 512.661.3843.

Frequently asked questions

Sources

• Fannie Mae Selling Guide Announcement SEL-2026-08 (Sept 2, 2026, updated Sept 23)
• Fannie Mae Selling Guide B3-3.8-05, Rental Income from Non-Subject Property: Departing Residence
• National Mortgage Professional, Fannie Changes How Rent From A Former Home Counts (Sept 22, 2026)
• TENA, Fannie Mae update to SEL-2026-08 implementation date
• Legal Clarity, Texas Home Equity Loan Rules and Notice Requirements
• Alston & Bird, Texas Home Equity Loan Amendments Enacted (Dec 2017)
• CLA, Texas Amends Provisions Regarding Home Equity Lending (7 TAC 153, eff. Mar 29, 2018)
• National Mortgage Professional, Texas Home Equity Loans Q&A
• Bankrate, HELOC rates
• Mortgage Professional America, Oct 19, 2026
• Norada, Interest Rate Predictions October 2026
• Serendipity Realty Group at Compass via openPR, Oct 19, 2026
• Team Price, Austin Housing Market Oct 15, 2026 and Oct 8, 2026
• CultureMap Austin, Sept 17, 2026 (Redfin buyer's-market report)
• The Real Deal, Oct 21, 2026 (Reisor Team Weekly Luxury Report) and Oct 14, 2026
• JVM Lending, Buy Before You Sell Programs Compared: 2026 Guide
• Real Estate Witch, Knock review and Clever, Knock Bridge Loan review
• AnytimeEstimate, Homeward review and How to Buy a House Before You Sell Yours
• FHFA Working Paper 23-06, Fonseca and Liu, The Lock-In Effect of Mortgage Rates
• Redfin analysis of FHFA National Mortgage Database
• Echelon analysis of Unlock MLS trailing-12-month data via Agent Intel (through Aug 31, 2026)

Related reading

• Upgrading to a luxury home in Austin
• Should I sell my house now or wait?
• Assumable mortgages in Austin
• Austin home prices by ZIP code
• Austin housing market forecast 2027
• How to buy a home in Austin's buyer's market
• Private listings in Austin
• MUD and PID taxes in Austin
• Texas as a non-disclosure state

About the author. Taylor Sherwood is the founder and principal REALTOR of Echelon Property Group, brokered by eXp Realty (TREC #734520), with $155 million-plus in career sales across 200-plus transactions. He holds the CLHMS Guild, GRI and ABR designations. Read more on the Taylor Sherwood page or reach him at 512.661.3843.