Comparative Market Analysis Explained for Buyers and Sellers

Ask three sources what your home is worth and you may get three different numbers: one from an online estimate, one from a real estate agent and, if you are refinancing or selling, one from an appraiser. The agent's number usually comes from a comparative market analysis, or CMA. Understanding how a CMA is built helps you judge whether a pricing recommendation is solid, whether you are buying or selling.

What is a comparative market analysis?

A CMA is a report that estimates a home's likely market value by comparing it with similar nearby properties that recently sold, along with homes that are currently for sale or under contract. In plain terms, "CMA" in realtor language means "here is what similar homes have sold for, here is how yours differs, and here is the price range that suggests."

Agents prepare CMAs for sellers deciding on a list price and for buyers deciding what to offer. They are usually free, because they are part of how an agent wins or serves a client. A CMA is an opinion of value, not an appraisal, and agents in most states are not permitted to call it an appraisal.

How agents choose comparable sales

The quality of a CMA depends mostly on the comps. Agents typically pull data from the MLS and public records, then filter for homes that a buyer would realistically consider alongside yours. Common criteria include the following, though the right ranges depend heavily on the market.

• Recency. Sales within roughly the last three to six months are preferred. In slow or rural markets, an agent may need to go back further and explain why.
• Proximity. Same subdivision or neighborhood first. In dense suburbs, comps may come from within a mile or less. In rural areas, they may be several miles away.
• Size. Similar finished square footage, often within a modest percentage of your home.
• Property type and style. Single-family with single-family, condo with condo, ranch with ranch where possible.
• Age and condition. Similar era of construction and level of updating.
• Bedrooms, bathrooms and features. Garages, basements, pools and lot size all matter.
• Location factors. School attendance zones, busy roads, water or golf frontage, and views can change value significantly.

Good CMAs also include active listings (your competition), pending sales (the most current signal of what buyers are paying, though final prices are often not public until closing), and sometimes expired or withdrawn listings, which show what prices did not work.

How adjustments work, with an example

No two homes are identical, so agents adjust each comp's sale price to account for differences. The rule is simple: adjust the comp to make it look like your home. If the comp has something better, subtract value. If the comp is missing something your home has, add value.

Here is a simplified example for a 1,900-square-foot home with three bedrooms, two baths, a two-car garage and an original kitchen. The dollar adjustments are illustrative only; real adjustments vary by market and price point, and agents often derive them from local sales data.

The adjusted values cluster between $389,000 and $401,000. An agent might weight Comp C most heavily if it is the most similar and most recent, then suggest a range of about $395,000 to $400,000. Notice that the raw sale prices spanned $27,000, while the adjusted values span $12,000. That tightening is a sign the comps and adjustments are doing their job.

One common mistake is relying on average price per square foot alone. Larger homes often sell for less per square foot than smaller ones, and features like a renovated kitchen or a lot backing to woods do not show up in a per-foot number.

CMA vs appraisal vs automated estimates

These three tools answer similar questions for different purposes.

Zillow Zestimate, Redfin Estimate and Realtor.com estimates

Online estimates are automated valuation models. They use public records, past sales and listing data to produce a number for nearly every home. Zillow and Redfin each publish information about their estimates' accuracy, and that information generally shows estimates are more accurate for homes that are currently listed for sale than for off-market homes. Realtor.com displays estimates from more than one data provider, which can help you see how much the models disagree.

People often ask whether Realtor.com or Zillow is more accurate. There is no single answer. Accuracy varies by provider, region and property type, and it can change as models are updated. Automated estimates tend to work best in neighborhoods with many similar homes and frequent sales, and worst for unusual, rural, recently renovated or poorly documented properties. Treat them as a starting point for questions, not a price.

How to read a CMA, step by step

1. Check the subject property details. Make sure square footage, bedrooms, bathrooms, lot size and upgrades are correct. Errors here ripple through everything.
2. Look at the comp map. Are the comps truly in comparable locations, or are some across a major road, school boundary or neighborhood line?
3. Check the dates. Older sales may not reflect current conditions if prices have moved.
4. Read the adjustments. Ask how each adjustment was chosen. Unexplained large adjustments deserve a question.
5. Compare sold, pending and active. If active listings are priced well above recent sales and not selling, that tells you something.
6. Look at days on market and list-to-sale ratios. These show whether homes sold quickly near list price or needed reductions.
7. Focus on the range, not just one number. A credible CMA explains why your home belongs at a certain point in the range.

Why two agents' CMAs can disagree

Sellers who interview several agents are sometimes surprised when the suggested prices differ by a meaningful amount. That does not necessarily mean someone is wrong. Common reasons include:

• Different comp choices. One agent may include a sale from the next subdivision that another considers less comparable.
• Different views on condition. How much a dated kitchen or new roof is worth is partly judgment.
• Different reads on the trend. In a rising or falling market, agents may weigh pending sales and recent price cuts differently.
• Different strategies. Some agents recommend pricing slightly below market to attract more buyers; others prefer to start higher.

Ask each agent to explain the gap using specific comps. The one who can do that clearly is usually giving you the more reliable number.

Getting comps without a realtor

If you are selling by owner or just curious, you can gather some data yourself. County assessor and recorder websites often show recorded sale prices, though some states do not require sale prices to be publicly disclosed. Major home search sites show recent sales in many areas. What you will usually not get is full MLS detail, such as condition notes, concessions and interior photos at the time of sale. Some buyers and sellers order a pre-listing appraisal for an independent opinion.

CMA review checklist

• Subject property facts are correct.
• At least three to six relevant sold comps, ideally recent and nearby.
• Active and pending listings included for context.
• Each adjustment is explained and reasonable for the local market.
• Adjusted values fall in a reasonably tight range.
• Days on market and list-to-sale price trends are shown.
• Seller concessions on comps are noted where known.
• The agent explains where in the range your home belongs and why.
• You compared the CMA with at least one other opinion, such as a second agent's CMA.

The takeaway

A CMA is only as good as its comps and the reasoning behind its adjustments. Ask your agent to walk you through it line by line. A solid analysis should leave you understanding not only what price is recommended, but why buyers in your market are likely to agree.

This guide is general information, not legal, tax or financial advice. Rules differ by state; confirm details with a licensed professional or your state real estate commission.