Home Equity

Home equity is the value of a property minus the debts secured against it. On a house appraised at $500,000 with a $300,000 mortgage, the equity is $200,000, and if a second lien of $50,000 is also recorded, the equity is $150,000. That is the whole calculation.

What makes the concept slippery is not the subtraction but the first term. A property does not have one value; it has several, produced by different processes for different purposes, and they routinely differ by tens of thousands of dollars. So a homeowner told they "have $150,000 of equity" has not yet been told anything actionable, because the figure that governs a mortgage insurance cancellation is not the figure that governs how much a lender will advance, and neither is the figure a sale would produce.

Equity is also a residual, not a holding. It is the leftover after two other quantities are set, and only one of them, the debt, responds to anything the owner does. The other moves with the market. That is why equity can fall while the owner makes every payment on time, and why it can be negative. How equity builds in the first place, from the down payment, the amortization of the loan and appreciation, is covered in the guide to real estate.

The four valuations, and what each one governs. Setting them side by side is what makes the concept usable, because each one is the answer to a different question.

Original value is what the property was worth when the loan was made, and it is the basis for the statutory right to cancel private mortgage insurance. Both the borrower's right to request cancellation at 80 percent and the servicer's duty to terminate automatically at 78 percent are measured against that figure rather than against a current appraisal, so appreciation does not get a borrower there by itself. The published material on private mortgage insurance sets out the conditions in full.

A current appraisal is what a lender uses when deciding how much to advance against the property today. It is the basis for a home equity loan or line of credit limit, and it is the number that responds to a renovation or to a rising market.

Assessed value is what a local assessor places on the parcel for tax purposes. It may be a fraction of estimated market value, it may be updated on a multi-year cycle, and it may be constrained by rules on how fast it can rise, so it is frequently the furthest of the four from any price a buyer would pay.

Net sale proceeds are what a sale actually produces, which is the price a buyer pays minus the costs of selling. This is the only one of the four that converts equity into money, and it is always the lowest for a given price, because the costs come out of it.

Lenders describe the same quantity from the other end, and the two ratios are worth keeping straight. Loan-to-value is the balance on the first mortgage divided by the value; combined loan-to-value adds every lien secured by the property. A lender considering a second lien cares about the combined figure, because that is what determines how much of the property is already committed. A ceiling expressed as 85 percent combined loan-to-value is the same statement as "we will leave 15 percent of the value as a cushion," and the cushion exists because a forced sale in a falling market recovers less than an appraisal suggests. So wherever the ceiling sits below 100 percent, the borrowable share is smaller than the equity, and the size of the cushion is the lender's decision rather than the borrower's.

Negative equity is not a separate concept. When the debt exceeds the value the same subtraction returns a negative number, and the practical consequences follow directly: a sale does not clear the loan, refinancing is generally unavailable because there is no cushion to lend against, and a borrower who has to move must find the shortfall in cash or negotiate with the lender. Nothing about the owner's behavior needs to change for this to happen. A large enough fall in local values does it while every payment is made on time, which is the clearest demonstration that equity is a residual rather than something the owner possesses.

The tax code uses the phrase for a different quantity, and conflating the two is the error. IRC 163(h)(3)(C)(i) defines "home equity indebtedness" as indebtedness other than acquisition indebtedness, secured by a qualified residence, to the extent it does not exceed "the fair market value of such qualified residence, reduced by ... the amount of acquisition indebtedness with respect to such residence." So the statute's version of equity is a borrowing capacity: how much additional secured debt can exist before the property runs out. It is measured against fair market value and against acquisition debt specifically, not against every lien and not against what the owner would net. It also no longer produces a deduction, because IRC 163(h)(3)(F)(i)(I) switches that limb off, permanently as of 2025. The definition matters here only because the same two words carry two meanings, and the reader who has met the tax phrase should not import it into a conversation with a lender.

Take the property's value, subtract every debt secured against it, and the remainder is the equity. To find what is borrowable instead, multiply the value by the lender's combined loan-to-value ceiling and subtract the existing liens. To find what a sale would produce, subtract the costs of selling from the price as well as the loan balance.

A hypothetical example, running one house through all four questions. Wren bought for $400,000 with $40,000 down, so the original value was $400,000 and the loan was $360,000. Five years on the balance is $322,000, a fresh appraisal comes in at $470,000, and the assessor's roll shows $355,000. Assume, for the illustration only, that the costs of selling would come to 8 percent of the price; what they actually come to depends on what is negotiated.

The headline figure is $470,000 − $322,000 = $148,000. This is what "your equity" usually means in conversation, and it is not the answer to any of the questions below.

Mortgage insurance. Cancellation runs against the original $400,000, where 80 percent is $320,000. The balance of $322,000 is above that, so Wren is not yet eligible to request cancellation, having built $78,000 of equity on that measure, which is 19.5 percent. The appraisal-based loan-to-value is meanwhile 68.5 percent ($322,000 ÷ $470,000), which sounds like a comfortable margin and is irrelevant to this particular right.

Borrowing. At a combined loan-to-value ceiling of 85 percent on the current appraisal, the lender will allow total liens of $399,500 ($470,000 × 0.85). Subtracting the existing $322,000 leaves $77,500 available, a little over half of the headline figure.

Property tax. The bill is computed on the assessed $355,000, a number that governs a real annual cost and has nothing to do with either the appraisal or the loan.

A sale. At $470,000 with selling costs of 8 percent, or $37,600, the sale nets $432,400, and after repaying the $322,000 balance Wren receives $110,400.

Four correct answers to "how much equity do I have," derived from one house on one day: $148,000, $78,000, $77,500 and $110,400. None of them is wrong. They answer different questions, and knowing which question you are asking is most of the skill in using the concept at all.

What home equity is good for

• It is the largest asset most households own, and it grows without any monthly contribution once the loan is amortizing.
• It can be borrowed against at rates well below unsecured credit, because the property secures the debt.
• It converts to cash on a sale, and a gain on a principal residence receives favorable tax treatment within statutory limits.
• It reduces the risk on the loan, which is what eventually ends a mortgage insurance requirement and improves refinancing terms.

The limits worth being clear about

• It is not liquid. Reaching it means selling, borrowing or a reverse mortgage, and each has costs the equity figure does not show.
• It can fall without any action by the owner, because one of the two inputs is the market.
• Only part of it is ever borrowable, since lenders keep a cushion below the full value.
• The number a homeowner quotes is usually the appraisal figure, which is the most flattering of the four and the one that governs the fewest decisions.
• Borrowing against it converts an asset that is hard to lose into a debt secured by the place you live, which changes what non-payment costs rather than only what it costs per month.