Capital Gains Tax on Your California Home Sale: What West Valley Sellers Need to Know

By Jason Franklin | July 15, 2026

Let's say you bought your home in West Hills in 2013 for $650,000. Today it's worth $1,400,000. You've been a homeowner for over a decade, you've taken care of the place, and now you're ready to sell.

Here's the question nobody warns you about before you call a real estate agent: how much of that $750,000 gain does California plan to take?

The answer depends on a few things — your filing status, your income, whether you've lived in the home long enough to claim the exclusion, and whether your gain exceeds it. But the most important thing to understand is this: California doesn't play by the same rules as the federal government when it comes to taxing home sale profits, and that difference is significant.

The Section 121 Exclusion: What It Covers and What It Doesn't

The federal tax code includes a provision called the Section 121 exclusion. It lets you exclude up to $250,000 in home sale gain from your taxable income ($500,000 if you're married and file jointly). California conforms to this rule — so the same exclusion applies on your state return.

To qualify, you need to have:

• Owned the home for at least 2 of the last 5 years
• Lived in it as your primary residence for at least 2 of the last 5 years
• Not used the exclusion on a different home sale within the prior 2 years

For most longtime West Valley homeowners, this isn't the problem. The problem is what happens when your gain is bigger than the exclusion.

Back to the West Hills example: a $750,000 gain minus a $500,000 exclusion leaves $250,000 taxable. That's real money — and in California, it's taxed at a rate that surprises most sellers.

The California Difference: Why This State Is Harder Than Most

Here's what most sellers don't know until it's too late to plan around it.

At the federal level, long-term capital gains (assets held more than one year) get a preferential tax rate — 0%, 15%, or 20% depending on your income. That's a meaningful break on a large gain.

California does not offer this. The state taxes capital gains as ordinary income, the same way it taxes wages and salaries. For high earners, that rate reaches 13.3% — 12.3% plus the 1% Mental Health Services surcharge on income above $1 million.

What does that mean in practice? For a seller in the higher income brackets, the combined tax burden on the taxable portion of a home sale gain can look like this:

• Federal long-term capital gains rate: 20%
• Net Investment Income Tax (NIIT): 3.8%
• California ordinary income rate: up to 13.3%
• Combined: up to 37.1%

On $250,000 of taxable gain, that's potentially $92,750 going to the federal and state governments. Your actual number will be lower if you're in a lower income bracket — but the point is that this isn't a rounding error. It changes your net significantly.

This is exactly the kind of calculation I walk my sellers through before we even talk about list price. Your net sheet isn't just commission and transfer taxes. It includes your capital gains exposure.

What Factors Affect Your Exposure

Not everyone faces the top rate. A few things determine where you land:

Filing status. A married couple gets $500,000 in exclusion; a single filer gets $250,000. If you jointly owned and occupied the home but one spouse passed away, you may still be eligible for the full $500,000 exclusion if you sell within two years of the death.

Your total income in the year of the sale. Capital gains push your taxable income higher, which can move you into a higher bracket — both federally and in California. Timing the sale for a lower-income year (retirement, a career gap, between businesses) can meaningfully reduce your exposure.

Improvements you've made. Every dollar you spent on capital improvements to the home — additions, a new roof, a remodeled kitchen, a permitted ADU — increases your adjusted cost basis and reduces your taxable gain. Keep your receipts. Most sellers underestimate how much they've spent over 10–20 years of ownership.

Selling costs. Agent commissions, escrow fees, title, transfer taxes, and closing costs can all be deducted from your proceeds when calculating your gain. Your net proceeds after selling costs — not your gross sale price — is the starting point for the gain calculation.

If you owned and were prepped to sell a home in the downsizing phase of life, these factors interact in ways that a CPA and a good net sheet can quantify clearly. Every situation is different, and the only way to know your actual exposure is to run the numbers specific to your property.

What to Do Before You List

The worst time to find out about a large capital gains liability is during escrow — or worse, after you've already closed. Here's the sequence I recommend to every seller considering a move:

Step 1: Call a CPA before you call an agent. Or at least in the same week. Your accountant can calculate your adjusted cost basis (purchase price plus capital improvements, adjusted for depreciation if the property was ever rented), estimate your federal and state tax exposure, and flag any strategies worth considering — like timing the close date or a potential installment sale structure.

Step 2: Request a detailed net sheet. A net sheet isn't just a back-of-the-envelope estimate. It should include the estimated sale price, all closing costs (escrow, title, commissions, transfer taxes), and your expected tax liability — so you know exactly what's coming your way at the end of the transaction. If you're selling a home in unincorporated Woodland Hills, you'll pay the county Documentary Transfer Tax but not the additional City of LA transfer tax — that matters on a $1.2M+ sale.

Step 3: Understand Measure ULA if you're in the luxury range. If your home is in the City of LA (not just LA County) and your transaction closes above $5,400,000, you'll owe the Measure ULA mansion tax — 4% on the entire sale price. As of July 1, 2026, the thresholds were updated upward, but the tax still creates a significant "cliff effect" near the threshold. This is a transfer tax, not a capital gains tax, but it affects your net the same way.

Step 4: Understand your Prop 19 situation. If you're planning to transfer your property tax base to a new home using Prop 19, that planning runs parallel to — and is completely separate from — capital gains planning. Both conversations should happen before you list.

Frequently Asked Questions

What is the Section 121 exclusion and do I qualify when selling my California home?

Section 121 is a federal tax rule that lets you exclude up to $250,000 in home sale gains from your taxable income if you're single, or $500,000 if you're married filing jointly. To qualify, you must have owned and lived in the home as your primary residence for at least 2 of the last 5 years — and you can't have used the exclusion on a different home sale within the prior 2 years. California conforms to this rule, so the same exclusion applies on your state return.

Does California offer a lower tax rate on capital gains, like the federal government does?

No — and this surprises a lot of sellers. The federal government taxes long-term capital gains at a preferential rate of 0%, 15%, or 20% depending on your income. California does not. The state taxes all capital gains as ordinary income at regular income tax rates, which go as high as 13.3%. That means a California seller in the top bracket pays a combined federal and state rate as high as 37.1% on any gain that exceeds the Section 121 exclusion.

What happens if my gain on my West Valley home exceeds the $500,000 exclusion?

The amount above the exclusion is taxable. For example, a married couple who bought in West Hills for $650,000 in 2013 and sells for $1,400,000 today has a $750,000 gross gain. After subtracting the $500,000 exclusion, $250,000 is taxable — subject to federal long-term capital gains tax (15–20%) plus California's ordinary income tax rate (up to 13.3%) plus the 3.8% Net Investment Income Tax if your income exceeds the NIIT threshold. Talk to your CPA before listing so you know your actual exposure.

I've owned my home for more than two years. Does a longer hold time reduce my capital gains tax in California?

A longer hold time qualifies you for federal long-term capital gains rates (vs. short-term rates, which match ordinary income rates), but it doesn't reduce your California taxes — the state taxes all capital gains as ordinary income regardless of how long you've held the property. What a long hold does do is usually mean more appreciation, which increases the chance your gain will exceed the Section 121 exclusion.

Can I use a 1031 exchange to defer capital gains when selling my home?

Not for a primary residence. A 1031 exchange is a tax-deferral strategy available for investment and business property — it allows you to roll proceeds from one investment property into another without triggering immediate capital gains tax. It does not apply to your personal home. If you're selling a rental property or investment property in the West Valley, a 1031 exchange may be worth discussing with your CPA. For your primary residence, the Section 121 exclusion is the relevant tool.

Capital gains tax is one of the most important — and most underestimated — parts of any significant home sale in California. Understanding your exposure before you list gives you time to plan, to time the sale strategically, and to build an accurate picture of what you'll actually walk away with.

I work with sellers across Woodland Hills, West Hills, Tarzana, Encino, and the surrounding West Valley every week, and I'm happy to walk you through what this looks like for your specific home. I can't give you tax advice — that's your CPA's job — but I can build you a detailed net sheet that accounts for your selling costs, transfer taxes, and estimated net proceeds so you go into that conversation with your accountant with the numbers that actually matter. Reach out anytime if you'd like to talk through your situation.