Buying Out Your Spouse on a $1M Home: Refinance Mechanics, Tax Basis Carryover, and the 5-Year Look-Back

The basic buyout math: equity, mortgage, and the refinance

Consider an Austin couple ending a 12-year marriage. They own a home with a current market value of $1,000,000 and an existing mortgage balance of $400,000. The equity is $600,000. The decree provides that the wife will keep the home and buy out the husband’s 50% equity share — $300,000.

The mechanical sequence:

1. Establish market value: a professional appraisal sets the value. Lenders require this for the cash-out refinance. Typical cost: $500-$800.
2. Calculate equity: market value minus existing mortgage = $600,000.
3. Calculate buyout: spouse’s share of equity = $300,000 (assuming 50/50 community or equitable split).
4. Refinance the mortgage: the wife refinances into her own name, simultaneously pulling cash out to fund the buyout. New loan: $400K existing + $300K buyout + $20K closing costs = $720,000.
5. Pay off the original mortgage: $400K paid to existing lender at closing.
6. Pay the buyout: $300K transferred to the husband from the new loan proceeds at closing.
7. Deed transfer: husband executes a quitclaim deed transferring his 50% interest to the wife. Title is now solely in her name.

The husband walks away with $300K in cash, tax-free under IRC § 1041. The wife owns the home outright with a $720K mortgage. The closing typically takes 30-45 days from contract.

The carryover basis trap: why $300K paid in buyout is NOT added to basis

The single most expensive misunderstanding in divorce buyouts is how the receiving spouse’s tax basis is calculated. Under IRC § 1041 and Treas. Reg. § 1.1041-1T(d), the receiving spouse takes the transferring spouse’s carryover basis — not a stepped-up basis to fair market value.

Continuing the example: the couple originally purchased the home in 2014 for $400,000, plus $50,000 of qualifying capital improvements (full kitchen remodel in 2019, new roof in 2022). The total original basis is $450,000. Each spouse’s 50% share of basis: $225,000.

After the buyout, the wife’s basis in the home is:

• Her original 50% share of basis: $225,000
• Plus the husband’s 50% share, transferred under IRC § 1041 with carryover basis: $225,000
• Total: $450,000

Note: the $300,000 the wife paid to the husband in the buyout does NOT add to her basis. The IRC § 1041 transfer is tax-free precisely because the basis carries over — the payment is treated as a property settlement, not a purchase. Treas. Reg. § 1.1041-1T(d) is explicit: “The transferor in a transaction described in section 1041 shall recognize no gain or loss. The transferee’s basis in such property shall be the adjusted basis of the transferor.”

Why this matters: when the wife eventually sells the home for, say, $1.2M five years later, her gain is calculated as:

• Sale price: $1,200,000
• Wife’s basis: $450,000 (NOT $750,000)
• Gain: $750,000
• IRC § 121 exclusion: $250,000 (single filer)
• Taxable gain: $500,000
• Federal LTCG (20%) + NIIT (3.8%) at high-income bracket: approximately $119,000 federal tax
• State tax (Texas: $0; California: ~13.3% on $500K = $66,500)

The wife is shocked at sale to discover she owes $119K-$185K in federal+state tax on what she thought was a routine sale of her home. The error: she assumed her basis was $750K ($450K + $300K paid in buyout) and the gain on a $1.2M sale would be $450K — entirely within the IRC § 121 exclusion as a single filer. The $300K never added to her basis.

IRC § 121 mechanics post-divorce: the ownership and use tests

The IRC § 121 primary residence exclusion is one of the largest tax breaks in the code: up to $250,000 of gain excluded for single filers, $500,000 for married filing jointly. To qualify, the seller must have owned AND used the home as their primary residence for at least 2 of the 5 years preceding sale.

For divorcing couples, IRC § 121(d)(3) provides a critical tacking rule:

• Ownership tacking: the period during which the divorcing spouse owned the home counts toward the buying spouse’s ownership test.
• Use tacking: the period during which the divorcing spouse used the home as their primary residence counts toward the buying spouse’s use test.

Practical effect: if the couple jointly owned and lived in the home for 8 years before the divorce, the buying spouse satisfies the 2-of-5 test the day after the divorce. Selling immediately post-buyout would still qualify the buying spouse for the $250K exclusion as a single filer.

However, the $500K joint exclusion is gone. If the home has $600K of unrealized gain at divorce, selling jointly before the decree would exclude the entire gain ($500K joint + maybe a small remainder taxable). Selling after the decree, each ex-spouse claims their separate $250K exclusion — total exclusion is the same $500K combined, but only if the bought-out spouse takes a share of the property and sells separately. If the buying spouse takes the whole property and later sells, only their $250K is excluded.

The 5-year look-back: timing your post-divorce sale

Several IRC § 121 rules involve a 5-year look-back from the date of sale. The most important ones for divorcing couples:

• 2-of-5 ownership test: must have owned the home for 2 of the 5 years before sale.
• 2-of-5 use test: must have used the home as primary residence for 2 of the 5 years before sale.
• Once-every-2-years limit: the § 121 exclusion can only be used once every 2 years.
• Partial exclusion for unforeseen circumstances under IRC § 121(c)(2): if a sale within 2 years of acquisition is forced by job change, health, or other unforeseen circumstances (including divorce decree mandate), a partial exclusion is available.

For a buying spouse who takes the home in divorce and later wants to sell, the timing analysis:

• Selling within 1 year post-divorce: ownership and use tacking from prior marriage typically satisfies the 2-of-5 test. Full $250K exclusion available if no IRC § 121 use in prior 2 years.
• Selling 1-2 years post-divorce: similar analysis; tacking still operative.
• Selling 2-5 years post-divorce: typically full exclusion available; the tacked-on pre-divorce ownership combined with post-divorce ownership comfortably exceeds the 2-year test.
• Selling 5+ years post-divorce: the 5-year look-back window now includes only post-divorce ownership and use. Provided the buying spouse owned and used the home for 2+ years post-divorce, exclusion qualifies. The pre-divorce period is no longer in the look-back window.

Refinance options in 2026 mortgage market

The buying spouse’s monthly carrying cost depends entirely on the refinance terms. As of mid-2026, the rate environment has shifted from the 4-5% range of the early 2020s to 6.5-7.5% for prime borrowers on conforming and jumbo loans.

Carrying cost comparison on a $720K loan (the example above):

• 30-year fixed at 7.0%: principal+interest = $4,789/month. Total interest over 30 years: $1,003,915.
• 15-year fixed at 6.5%: principal+interest = $6,266/month. Total interest over 15 years: $407,909.
• 5/1 ARM at 6.25% initial: principal+interest = $4,431/month for first 5 years; resets to market rate thereafter.

Alternative buyout structures when refinancing is not optimal:

• Assume the existing mortgage: if the existing loan is assumable (rare for conventional loans, common for VA and FHA), the buying spouse may keep the existing 4.5% rate. Most conventional mortgages are NOT assumable in divorce without lender approval and re-underwriting.
• Home equity line of credit (HELOC): take a HELOC on the existing home to fund the buyout, leaving the original mortgage in place. Requires the bought-out spouse’s consent to delayed deed transfer (since the HELOC underwrites on combined credit).
• Promissory note to the ex-spouse: the buying spouse signs a note to the ex-spouse for the buyout amount, secured by a second deed of trust on the home, paid over 5-10 years. Avoids immediate refinance costs but creates ongoing creditor relationship between ex-spouses — risky if relationships deteriorate.
• Offset with other marital assets: instead of a cash buyout, the buying spouse gives up an equivalent value of other assets (401(k) via QDRO, brokerage, business interests) to the ex-spouse. No refinance needed if existing mortgage stays in place (subject to lender notification requirements).

Removing the ex-spouse from the mortgage: non-optional

The most overlooked operational point in divorce buyouts: even after the deed transfers, the ex-spouse remains liable on the original mortgage unless the mortgage is paid off or refinanced. Most family law attorneys understand this; many divorcing couples don’t.

Consequences of leaving the ex-spouse on the mortgage:

• The mortgage appears on the ex-spouse’s credit report. Late payments by the buying spouse damage the ex-spouse’s credit.
• The mortgage counts in the ex-spouse’s debt-to-income ratio when they apply for a new mortgage on a different property.
• If the buying spouse defaults, the lender can pursue the ex-spouse for the deficiency.
• In some states, the lender can name both ex-spouses in foreclosure proceedings even years post-divorce.

The non-negotiable requirement: the divorce decree should mandate that the buying spouse refinance into their own name within a specified period (typically 60-90 days from decree). If the buying spouse cannot qualify on their own income alone, the home should be sold rather than retained.

State-specific notes for high-tax-bracket sellers

For divorcing couples in high-tax states selling a home that appreciated significantly:

• California: state taxes capital gains as ordinary income, up to 13.3%. On a $500K taxable gain (post-divorce single $250K exclusion), state tax can add $66,500 to federal liability.
• New York: top state rate 10.9%; NYC adds another 3.876%. Total state+local can hit 14.776% on capital gains.
• New Jersey, Oregon, Hawaii: all in the 10%+ top-bracket range.
• Texas, Florida, Nevada, Washington (no income tax): federal tax only on the gain. Washington has a 7% long-term capital gains tax above $250K under the 2022 statute, but the primary residence exclusion under IRC § 121 generally exempts the gain.

The basis-tracking spreadsheet (the document most divorcing homeowners should keep)

After a buyout, the buying spouse should maintain a documented record of basis. Key items:

• Original purchase price + transaction costs (recording fees, title insurance) at acquisition
• Date of acquisition and how titled (joint tenancy, tenancy in common, community property)
• Qualifying capital improvements with dates and amounts (kitchen remodels, additions, new roofs, HVAC) — receipts and contractor invoices retained
• Non-qualifying repairs and maintenance (excluded from basis) — for clarity, not for tax tracking
• The IRC § 1041 divorce transfer date and the post-transfer basis (carryover from transferring spouse)
• Any post-divorce capital improvements with dates and amounts
• Eventual sale date, sale price, and selling costs (commission, recording, title)

The exclusion calculation at sale is: (sale price − selling costs) − (purchase price + improvements + carryover basis) − IRC § 121 exclusion = taxable gain. The IRS can challenge basis calculations, and the burden of proof falls on the seller. Without documentation, the IRS treats basis as zero, taxing the entire sale proceeds as gain. This is a five- to six-figure risk that’s entirely preventable.

Key takeaways

• Buying out a spouse on a home is a tax-free transfer under IRC § 1041. The transferring spouse owes no capital gains tax; the buying spouse takes carryover basis.
• The cash paid in the buyout does NOT add to the buying spouse’s basis. The original purchase price and capital improvements transfer in full from the ex-spouse’s share.
• Post-divorce, the buying spouse is a single filer limited to the $250K IRC § 121 exclusion — down from the $500K available to married couples filing jointly. For homes with $500K+ of gain, the timing of sale matters.
• The 5-year look-back rules under IRC § 121 permit tacking of the ex-spouse’s ownership and use, allowing immediate post-divorce sale to qualify for the exclusion.
• The refinance to remove the ex-spouse from the mortgage is mandatory — leaving them on creates ongoing liability and credit exposure for the ex-spouse.
• Maintain a basis-tracking spreadsheet from the divorce forward. The IRS can challenge basis at sale, and undocumented basis is treated as zero.