US Mortgage Appraisals Shift to Structured Data as CMA Process Faces Scrutiny
United States | October 21, 2026: A major change in how residential properties are valued in the US mortgage market is set to take effect on November 2, when Fannie Mae and Freddie Mac move residential appraisal reporting toward structured, MISMO-aligned data.
The shift could have an impact beyond lenders and appraisers. It may also expose a growing gap between the comparative market analysis (CMA) used by real estate agents to establish asking prices and the appraisal that later determines how a property is assessed for lending purposes.
Appraisals are moving from forms to structured data
The upcoming transition changes the way residential appraisal information is presented and processed. Instead of relying primarily on traditional report forms, appraisal information will be organised as structured data aligned with the MISMO reference model.
This means individual property characteristics and valuation elements can be recorded as separate data fields, making them easier to analyse, compare and validate.
For lenders, the change is designed to create a more flexible and data-driven appraisal process across different types of residential properties.
For the wider property market, however, the more significant question may be what happens when this level of transparency is compared with the information contained in a typical CMA.
The CMA usually comes before the formal appraisal
A property's first major valuation often happens before an appraiser visits the home.
When a homeowner decides to sell, a real estate agent typically prepares a CMA using comparable recent sales, property characteristics and local market conditions. That analysis helps determine the initial asking price and shapes the seller's expectations.
The CMA may include adjustments for factors such as size, bathrooms, age, condition and other property characteristics.
But the methodology behind those adjustments is not always visible from the final document. An adjustment can be based on market analysis, statistical modelling, comparable transactions or a consistent rate applied across properties.
The resulting document can therefore look precise even when the underlying calculation is not immediately inspectable by someone outside the valuation process.
Why adjustment methodology matters to property prices
Not every adjustment in a CMA needs to come from a direct comparison between two nearly identical properties.
Paired-sales analysis is one recognised approach, but finding two transactions that differ by only one meaningful characteristic can be difficult, particularly in neighbourhoods where homes have undergone different renovations or have significantly different layouts.
Other analytical approaches can also be used to determine how buyers respond to differences between properties.
The important issue is whether the adjustment reflects actual market behaviour and can be reasonably supported. The challenge is that the final CMA may not clearly communicate how each figure was established.
The appraisal will become easier to inspect
The move toward structured appraisal data changes that dynamic.
When property characteristics, comparable sales and adjustments are captured as discrete data points, they can potentially be examined individually rather than only through a finished report.
That creates a more transparent framework for analysing how an appraiser reached a valuation.
It could also make differences between the agent's initial pricing analysis and the lender's appraisal easier to identify. Instead of simply comparing two valuation figures, market participants may increasingly be able to examine the underlying inputs that produced them.
A wider gap could emerge between asking price and appraised value
The difference between a CMA and an appraisal has always been important, particularly when an appraisal comes in below the agreed purchase price.
The upcoming data transition could make that difference more visible.
A seller may have received a CMA supporting a particular asking price, while the eventual appraisal could arrive with a structured set of property and comparable-sale data supporting a different value.
For buyers, sellers and agents, the conversation could increasingly move from “Why is the appraisal different?” to “Which specific market evidence produced each valuation?”
That could change how pricing disputes are handled during transactions.
What this means for buyers and sellers
For sellers, the change reinforces the importance of understanding how an asking price is established rather than relying solely on a headline valuation.
Buyers may also benefit from examining the comparable sales and property characteristics behind a valuation, particularly when the appraisal differs materially from the contract price.
For real estate professionals, the shift could create pressure for CMAs to become more data-driven and transparent if structured appraisal information becomes the industry norm.
The immediate change is happening within the mortgage appraisal process, but its influence could eventually extend to the way residential properties are priced before they even reach the appraisal stage.
What happens next
The transition begins on November 2, 2026, as residential appraisal reporting moves toward the new structured-data framework.
The bigger question for the housing industry will be whether the CMA evolves alongside it.
If appraisals become increasingly searchable, standardised and data-driven while listing valuations continue to rely on document-based analyses, the difference between the two could become much easier for buyers, sellers, lenders and agents to see.
That could ultimately push residential pricing toward greater consistency — and greater scrutiny of the numbers used to establish a home's value in the first place.