A capital gain is not the price you sell for

A lot of people get this wrong, and it is the most expensive misunderstanding in a home sale. Your gain is the profit. Profit is your net sale price minus what the taxman calls your adjusted basis.

Your basis starts as what you paid for the house. Then you add to it. Every capital improvement you made over the years adds to your basis:

• A new roof
• A room addition
• A pool
• A new kitchen
• New HVAC
• New windows
• Solar you paid for
• A block wall
• Permitted work of real substance

Repairs do not count. Fixing a leaky faucet is not an improvement. Replacing the whole plumbing system is. You also add most of your buying and selling costs, things like your closing costs when you bought and your real estate commission, title, and escrow fees when you sell.

All of that raises your basis, and the higher your basis, the smaller your taxable gain.

Lesson one: keep your receipts

This is the one people ignore. Every improvement receipt you save is basis, and every dollar of basis is a dollar of profit the government cannot tax. If you did thirty years of work on a Santa Clarita house and you have no records, you just handed away the proof that would have lowered your tax.

The formula

Sale price, minus selling costs, gives you your amount realized.

Amount realized, minus your adjusted basis, gives you your gain.

How long you owned it decides the rate

If you owned the property one year or less, that is a short-term gain, and it gets taxed at ordinary income rates, the same as a paycheck. Almost nobody who lives in a home sells that fast, so for most sellers we are talking about long-term gains, which means you owned it more than a year, and long-term gains get the friendlier federal rates.

The Section 121 primary residence exclusion

Here is the biggest break in the whole tax code for a homeowner. If the home you are selling was your main home, and you owned it and lived in it as your primary residence for at least two years out of the last five years before the sale, you can exclude a huge chunk of gain from tax entirely.

• Single: exclude up to $250,000 of gain
• Married filing jointly: exclude up to $500,000 of gain

That is not a deduction. That is gain that simply never gets taxed, federal or California.

The two years do not have to be back to back. You just need twenty-four months of ownership and twenty-four months of living there inside that five-year window. There is a frequency limit: you can only use this exclusion once every two years, so you cannot flip primary residences every twelve months and keep claiming it.

And here is a number that surprises people. That $250,000 and $500,000 has not changed since 1997. It is not indexed to inflation. Home values in Santa Clarita have multiplied several times over since 1997, but that exclusion has stood still, which means more sellers today blow past it than ever did back then.

There are partial exclusions if you had to move early for a specific reason: a job relocation of far enough distance, a health problem, or certain unforeseen circumstances. In those cases you get a prorated piece of the exclusion based on how long you were there. Again, that is a conversation for your CPA.

Real Santa Clarita numbers, example one: the gain disappears

Say a married couple bought a house in Saugus back in 2004 for $525,000. Over the years they put in a new roof, a remodeled kitchen, new heating and air, and a pool, and they kept the receipts. That adds up to $75,000 of real capital improvements.

• Adjusted basis: $600,000
• They sell in 2026 for $1,150,000
• Commission and closing costs: about $70,000
• Amount realized: $1,080,000
• Gain: $1,080,000 − $600,000 = $480,000

They are married, they lived there the whole time, so they get the $500,000 exclusion. $480,000 is under $500,000. Their entire gain is excluded. They owe zero federal capital gains tax and zero California tax on that sale.

That is the power of the exclusion. And notice that the $75,000 in improvements they could prove is what kept them under the line.

Example two: change one number and the tax shows up

Same couple, same basis of $600,000, but the market runs hotter.

• They sell for $1,450,000
• Selling costs: $85,000
• Amount realized: $1,365,000
• Gain: $765,000
• Minus the $500,000 exclusion: $265,000 of taxable gain

That $265,000 is the part that gets taxed.

Federal rates in 2026

On the federal side in 2026, long-term capital gains sit in three buckets, and which bucket you land in depends on your total taxable income for the year, not just the gain.

Married filing jointly, 2026:

• 0% up to about $98,900 of total taxable income
• 15% from there up to about $613,700
• 20% above $613,700

Single filer, 2026:

• 0% up to about $49,450
• 15% up to about $545,500
• 20% above that

Most Santa Clarita sellers with normal working incomes are going to see that leftover gain taxed at the 15% federal rate. So on that $265,000 of taxable gain, at 15%, that is right around $39,750 of federal capital gains tax.

The second federal layer: the 3.8% NIIT

We are not done, because there is a second federal layer called the Net Investment Income Tax, the NIIT, and it is an extra 3.8%.

It hits when your modified adjusted gross income goes over $200,000 if you are single or $250,000 if you are married filing jointly. And just like the home exclusion, those thresholds have never been adjusted for inflation since they started in 2013. A big home-sale gain can push you over that line, and the 3.8% applies to the gain that sits above the exclusion, to the extent you are over the threshold.

So a high enough gain can carry both the 20% federal rate and the extra 3.8% on top.

Then comes California, and California does not play the federal game

California has no special lower rate for capital gains. None. The state taxes your capital gain exactly like ordinary income, like wages.

California brackets in 2026 run from 1% at the bottom all the way up to 12.3%, and there is an additional 1% mental health services surcharge on taxable income over $1,000,000, which pushes the true top rate to 13.3%, the highest state rate in the country.

Where your leftover gain lands in those brackets depends on your total California income for the year. For a lot of sellers, that added gain gets taxed somewhere in the 9.3% range at the margin, and for high earners it climbs higher.

The good news: California does honor the same Section 121 primary residence exclusion. That $250,000 or $500,000 you excluded federally is also excluded on your California return. It is only the leftover, the part above the exclusion, that California taxes as ordinary income.

The closing-table surprise: California Form 593 withholding

There is one more California item that catches sellers off guard at the closing table, and it is not actually a tax. It is a prepayment. It is called real estate withholding, and it runs on a form called Form 593.

When you sell California real estate, the state generally requires that 3 1/3% (3.33%) of the gross sales price be withheld at closing and sent to the Franchise Tax Board as a prepayment against whatever California tax you will owe. On a million dollar sale, that is $33,300 held back.

Here is the relief:

• If your sale qualifies for the primary residence exclusion, you can certify that on the form and be exempt from the withholding.
• Withholding is also not required when the sales price is $100,000 or less.
• Even when it does apply, it is not lost money, it is a deposit. It gets credited against your actual California tax when you file, and if too much was withheld you get it back.
• There is also an option to elect withholding based on the actual gain instead of the full sales price, which your escrow officer and your tax person can help you calculate if the flat 3.33% would over-withhold you.

If it is a rental, the rules change hard

If you are selling a rental property or an investment property, you do not get the Section 121 exclusion at all. That break is only for your main home.

And there is a second bite on a rental that people forget about, called depreciation recapture. When you own a rental, the IRS lets you, actually expects you, to depreciate the building, not the land, over 27.5 years for a residential rental. Each year of depreciation lowers your taxable rental income, but it also lowers your basis dollar for dollar.

So when you sell, all that depreciation you took, or were allowed to take, comes back as its own layer of gain called unrecaptured Section 1250 gain, and it is taxed at a federal rate of up to 25%, higher than the normal long-term rate.

And here is the part that stings. The IRS recaptures depreciation you were entitled to take even if you never actually took it, so there is no reward for skipping it. On top of that, California taxes that recaptured amount as ordinary income too.

So a rental sale can carry a 25% federal recapture layer, a 15% or 20% federal rate on the rest of the gain, the 3.8% NIIT, and the full California ordinary rate, all in the same year. That is exactly why investment sellers look at a 1031 exchange, which is its own whole conversation, because a properly done 1031 defers all of that.

Six strategies that actually move the needle

1. Keep every improvement receipt for as long as you own the property, because basis is the cheapest tax savings there is.
2. Know your dates. Owning and living in the home two of the last five years is what unlocks the exclusion, and selling one day too early can cost you a quarter million or a half million in shelter.
3. Mind the frequency rule, once every two years on the exclusion.
4. Time your sale with your income in mind when you can, because the same gain can sit in the 0%, 15%, or 20% federal bucket depending on your total income that year.
5. If it is investment property, look hard at a 1031 exchange before you sell, not after, because after you close it is too late.
6. The quiet one: stepped-up basis. When you die, your heirs get what is called a stepped-up basis. The property resets to its fair market value on the date of death, and all of that built-up gain, the whole thing, disappears for tax purposes. Which means for some owners the best tax move on a highly appreciated property is to hold it, borrow against it if they need liquidity, and let their heirs inherit it clean. That is not right for everyone, and it is a decision to make with a tax professional and an estate attorney, but it is real, and it is the reason wealthy families hold real estate for generations.

The whole picture in one paragraph

Your gain is sale price minus selling costs minus adjusted basis. Your primary residence can shelter $250,000 single or $500,000 married if you owned and lived there two of the last five years. Federal long-term rates are 0%, 15%, or 20% depending on income, plus a possible 3.8% surtax. California taxes whatever is left as ordinary income up to 13.3%, and holds back 3.33% at closing unless you are exempt. Rentals lose the exclusion and add depreciation recapture at up to 25% federal. And death resets the basis and wipes the slate. Run your own exact numbers with your CPA or tax attorney before you make a move, because this is your money and the details are where it lives.

Related Santa Clarita seller reading

• The Santa Clarita Homeowner Tax Guide, the yearly write-offs and cost-basis side of this same picture
• 1031 Exchange in Santa Clarita: benefits for sellers and buyers
• What is Mello-Roos in Santa Clarita?
• Selling a Mello-Roos home in Santa Clarita
• Mello-Roos vs HOA vs property tax in Santa Clarita
• Santa Clarita and Los Angeles County property tax reassessment by the numbers

Frequently asked questions

Do I pay capital gains tax when I sell my Santa Clarita home?

Only on the gain that exceeds your exclusion. If the home was your primary residence and you owned and lived in it two of the last five years, you exclude up to $250,000 of gain if single or $500,000 if married filing jointly, on both your federal and California returns. Many Santa Clarita sellers owe nothing at all.

How is the capital gain on a home sale actually calculated?

Sale price minus selling costs equals your amount realized. Amount realized minus your adjusted basis equals your gain. Your adjusted basis is what you paid, plus capital improvements, plus most buying and selling costs.

Does California have a lower tax rate for capital gains?

No. California has no preferential capital gains rate. The state taxes capital gains as ordinary income, with 2026 brackets running from 1% up to 12.3%, plus a 1% mental health services surcharge on taxable income over $1,000,000 for a top rate of 13.3%. California does honor the same Section 121 primary residence exclusion the federal government does.

Why is escrow holding back 3.33% of my sale price?

That is California real estate withholding on Form 593, a prepayment toward your state tax, not a tax itself. If your sale qualifies for the primary residence exclusion you can certify that on the form and be exempt. It is also not required when the sales price is $100,000 or less. When it does apply it is credited against your actual California tax at filing, and over-withholding is refunded.

Do I get the exclusion on a rental property?

No. The Section 121 exclusion applies only to your main home. A rental sale also triggers depreciation recapture, taxed federally at up to 25% as unrecaptured Section 1250 gain, and the IRS recaptures the depreciation you were entitled to take even if you never claimed it. A 1031 exchange, set up before you sell, is the usual way investment sellers defer all of it.

What happens to capital gains if I never sell and my heirs inherit the house?

They receive a stepped-up basis. The property resets to fair market value on the date of death and the entire built-up gain disappears for tax purposes. For some owners with highly appreciated property that makes holding, rather than selling, the strongest tax outcome. That is a decision for a tax professional and an estate attorney, not a blog post.

Connor MacIvor, The Sellers Only Agent, full-service listing model, Santa Clarita Valley. Thinking about selling and want the net-sheet conversation before the tax conversation? sellersonlyagent.com

Connor T. MacIvor · CalDRE #01238257 · Sync Brokerage, Inc. · DRE #02031490