Why Two Similar Portland Homes Can Have Completely Different Property Taxes

Shannon McLaughlin

8/3/20266 min read

a black and white photo of a house
a black and white photo of a house

A lil' Portland history detour: Many of the neighborhoods we now think of as some of Portland’s most desirable areas looked very different 30 or 40 years ago. In the 1980s and early 1990s, neighborhoods like Alberta, Mississippi, and parts of Northeast Portland had much lower home values than they do today. As interest grew in Portland’s older housing stock—partly because buyers recognized the craftsmanship and character that were difficult to replicate—these neighborhoods experienced dramatic changes in value.

A home that may have once been considered an affordable fixer-upper could later become a highly sought-after property. But while the market value changed quickly, Oregon’s property tax system was designed to slow how quickly taxable values could rise.

Measure 50 winners and losers - courtesy of The OregonianMeasure 50 winners and losers - courtesy of The Oregonian

Disclaimer: Property tax rules in Oregon can be complex, and every property’s situation is different. This article is for general educational purposes only and is not tax or legal advice. For questions about a specific property’s assessed value or tax bill, consult Multnomah County Assessment & Taxation or a qualified tax professional.

One of the questions I hear often—especially from buyers looking at older homes—is:

How can two houses that look almost identical have dramatically different property tax bills?

It’s a really fair question.

Imagine two beautifully restored early 1900s Craftsman homes sitting next door to each other. They’re the same size, in similar condition, and would likely sell for about the same price. Yet one homeowner may be paying thousands of dollars less in property taxes each year than the other.

The reason has less to do with the age of the homes and more to do with Oregon’s unique property tax system. Let’s get into it!

Measure 50 Changed How Oregon Calculates Property Taxes

In the 1990s, home values across Oregon were rising quickly, and property taxes were increasing along with them. Oregon voters first passed Measure 47 in 1990, which attempted to limit rising property taxes. After legal challenges, Measure 50 was approved in 1997, creating the system Oregon uses today.

Before Measure 50, property taxes were more closely tied to a home’s market value. As home prices increased, taxes often increased right along with them.

Measure 50 created a new system based on Maximum Assessed Value (MAV), which generally grows by no more than 3% per year unless certain changes are made to the property.

So How Are Property Taxes Calculated?

Every year, the county looks at two different values:

Real Market Value (RMV): What the property would likely sell for today.

Maximum Assessed Value (MAV): The value used to calculate property taxes.

Property taxes are based on whichever value is lower, which is know as your Assessed Value.

Here’s a simplified example:

A Portland home has:

  • Real Market Value (RMV): $900,000

  • Maximum Assessed Value (MAV): $450,000 (capped at 3% increase per year)

The property taxes are calculated using the $450,000 assessed value, not the $900,000 market value.

If the local tax rate is $15 per $1,000 of assessed value:

$450,000 ÷ $1,000 = 450
450 × $15 = $6,750 in annual property taxes

The exact rate varies depending on location and taxing districts, but the important takeaway is:

A home’s market value and taxable value are not always the same thing.

In conclusion...

As a real estate agent, I spend a lot of time helping people understand homes—their value, their history, and the choices that shape their future.

In Oregon, a home’s value is about more than what it would sell for today. The tax history, improvements, and decisions made over decades all become part of the story.

For anyone who loves Portland’s historic homes as much as I do, it’s another reminder that these houses carry layers of history—not just in their architecture, but in the systems that shape how we own and preserve them.

Historic Homes Tell the Story Best

Portland is full of neighborhoods where home values have changed dramatically over the last few decades—places like Alberta, Mississippi, Irvington, Sellwood, Mount Tabor, and Laurelhurst.

Imagine two nearly identical 1912 Craftsman homes.

The first has been owned by the same family for 30 years. They’ve maintained it beautifully, restored original details, and made thoughtful updates—but haven’t added significant square footage.

The second home has a similar market value today, but it had a major addition, finished attic, or ADU added over the years.

Both homes may sell for around $900,000 today, but their taxable values may be very different.

Why?

The first homeowner’s Maximum Assessed Value may have grown gradually over decades, while the second property may have additional taxable value from qualifying improvements.

This is why a longtime homeowner and a recent buyer can have very different tax situations—even when their homes appear almost identical.

Not Every Renovation Raises Your Taxes

A common question from owners of older homes is:

“Will this renovation increase my property taxes?”

The answer is: it depends.

Routine maintenance usually does not increase taxable value. Replacing a roof, restoring original windows, repainting the exterior, refinishing hardwood floors, or updating plumbing and electrical systems are all ways of caring for a home.

However, projects that create new living space—like additions, finishing unfinished areas, or building an ADU—may increase assessed value.

Understanding this before starting a renovation can help homeowners make informed decisions.

Buying a Home Doesn’t Reset Your Taxes…or does it?

Many buyers assume that when a home sells, property taxes are recalculated based on the purchase price.

That’s true in some states.

Not in Oregon.

A home sale does not automatically reset the property’s Maximum Assessed Value to the new purchase price. The existing tax history generally stays with the property.

However, a seller’s current tax bill does not always tell the whole story. Exemptions, deferrals, qualifying improvements, and future assessment changes can all affect what a future owner pays.

A surprisingly low tax bill may reflect a benefit available to the current homeowner but not the next one.

The lesson?

Don’t just look at the current tax bill—understand why it is what it is.

Built to last another 100 years: One of the reasons Portland’s older homes are so special is that many were built with materials and craftsmanship that are hard to reproduce today—old-growth wood, detailed millwork, plaster walls, and custom finishes. Restoring those features can add tremendous value to a home, but maintaining a historic property is often different from adding new square footage. A new roof and restored windows may preserve a home’s character without necessarily changing its taxable value the same way an addition or ADU might.

Historic Homes and Special Property TaxES

Some historically significant properties may qualify for Oregon’s Historic Property Special Assessment Program. But owning an old home does not automatically qualify—a 100-year-old Craftsman is not necessarily a “historic property” for tax purposes.

Generally, the property must have a recognized historic designation, such as being listed in the National Register of Historic Places, and owners must follow an approved preservation plan and ongoing requirements.

For qualifying properties, the benefit is tied to the property rather than just the current homeowner, so it may continue after a sale if the new owner agrees to continue meeting the requirements.

However, these benefits are not permanent. The special assessment has a limited term, and if the program expires or the property no longer qualifies, the tax bill may increase.

For buyers interested in historic homes, this is another reason to look beyond today’s tax bill and understand the story behind it.

Measure 50 was designed to give homeowners more stability by creating a buffer between rapidly changing home values (due to gentrification) and property taxes.

It especially benefited people who stayed in their homes as neighborhoods changed and property values increased.

But over time, it also created a new reality: two similar homes can have very different tax bills depending on when they entered the system.

Left: Measure 50 winners and losers, Courtesy of The Oregonian

LET’s LOOK CLOSER!

I’ve lived in the Pacific Northwest my entire life and have spent years helping people understand the many layers that make up our local housing market—from changing neighborhood values to the unique history behind Portland’s homes.

Whether you’re a first-time buyer trying to understand how homeownership works, or a longtime homeowner thinking about your next move, I’d love to help you make informed decisions that support your long-term goals.

THRIVE PORTLAND

Helping you navigate the wild world of real estate.

CONTACT

STAY IN THE LOOP

© 2026. All rights reserved.

Thrive Portland, LLC is licensed in the state of Oregon.

Shannon McLaughlin

Licensed Oregon Realtor®

Managing broker

2601 NE Glisan Street

Portland, Oregon 97232

FOLLOW ME

@THRIVEPORTLAND