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Martin Marietta MaterialsMIL:1MLM 92 Operating Margin % is 12.26% as of Mar. 2026, which is 37% below its 10-year median of 19.40. GuruFocus rates MIL:1MLM with a GF Score™ of 92/100 and a GF Value™ of €653.58. The stock has 3 warning signs investors should review. Among 403 Building Materials companies, Martin Marietta Materials ranks better than 88.83% on this metric.
Martin Marietta Materials Inc operating margin is expanding. Margin expansion is usually a good sign.
The historical rank and industry rank for Martin Marietta Materials's Operating Margin % or its related term are showing as below:
MIL:1MLM'
s Operating Margin % Range Over the Past 10 Years
Min: 16.59 Med: 19.4 Max: 23.66
Current: 22.7
MIL:1MLM's Operating Margin % is ranked better than 88.83% of 403
companies
in the Building Materials industry
Industry Median: 7.62
vs MIL:1MLM: 22.70
Martin Marietta Materials (MIL:1MLM) Operating Margin % Explanation
Just like Gross Margin %, it is important to see a company maintains its operating margin over time. Among the same industry, a company with higher operating margin is more efficient in its operation. It is also more stable during industry slowdown or recessions. Peter Lynch prefers those with higher margins than those with lower margins.
Be Aware
Operating Margin % can be manipulated by adjusting the rate of depreciation, depletion and amortization (DDA).
If a company is facing competition, its Operating Margin % may decline. Often the Operating Margin % declines well before the company's Revenue or even profit decline. Therefore, Operating Margin % is a very important indicator of whether the company is facing problems.
For instance, by 2012, Nokia (NOK)'s problems were well known and its stock had lost more than 90% of its market value since 2007. But Nokias Operating Margin % had already been in decline since 2002, although its Earnings per Share (Diluted) were still rising. Investors who paid attention to Operating Margin % would have avoided this huge loss. The same can be said for Research-in-Motion (RIMM).
Therefore, Operating Margin % is a very important screening filter for GuruFocus. GuruFocus's Buffett-Munger screener requires that the profit margin is either consistent or expanding. The Model Portfolio of the Buffett-Munger screener has outperformed the market every year since inception in 2009.
Martin Marietta Materials Operating Margin % Related Terms
Martin Marietta Materials Operating Margin % Historical Data
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
Martin Marietta Materials Operating Margin % Chart
MIL:1MLM vs VMC, JHX, EXP: Operating Margin % Comparison
For the Building Materials subindustry, Martin Marietta Materials's Operating Margin %, along with its competitors' market caps and Operating Margin % data, can be viewed below:
* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.
Martin Marietta Materials Operating Margin % vs Building Materials Industry
For the Building Materials industry and Basic Materials sector, Martin Marietta Materials's Operating Margin % distribution charts can be found below:
* The bar in red indicates where Martin Marietta Materials's Operating Margin % falls into.
Martin Marietta Materials Operating Margin % Calculation
Operating Margin % - also known as operating income margin, operating profit margin and return on sales (ROS) - is the ratio of Operating Income divided by net sales or Revenue, usually presented in percent.
Martin Marietta Materials's Operating Margin % for the fiscal year that ended in Dec. 2025 is calculated as
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
Martin Marietta Materials (MIL:1MLM) has a Operating Margin % of 12.26% as of Mar. 2026. Operating margin is the ratio of total operating income to net sales. View historical data on Martin Marietta Materials and its competitors. This is 37% below median its historical median of 19.40. Over the past decade, Martin Marietta Materials' Operating Margin % has ranged from 16.59 to 23.66. According to the industry distribution chart, Martin Marietta Materials ranks #45 out of 403 companies in the Building Materials industry, placing it in the top 11.2%.
Is Martin Marietta Materials' Operating Margin % too high?
Martin Marietta Materials' current Operating Margin % of 12.26% is 37% below median its 10-year median of 19.40. Over the past 10 years, this metric has ranged from a low of 16.59 to a high of 23.66. The Building Materials industry median Operating Margin % is 7.62. Martin Marietta Materials' value of 12.26% is 60.9% above this industry median. Based on the distribution chart, Martin Marietta Materials ranks #45 out of 403 companies in the Building Materials industry, which is in the top quartile — a strong position relative to peers. Overall, Martin Marietta Materials has a GF Score™ of 92/100, reflecting its overall financial health beyond just this single metric.
How does Martin Marietta Materials' Operating Margin % compare to VMC and JHX?
According to the Building Materials industry distribution chart, Martin Marietta Materials ranks #45 out of 403 companies for Operating Margin %. This places Martin Marietta Materials in the top 11% of its industry — outperforming the majority of peers. The industry median Operating Margin % is 7.62. Martin Marietta Materials' value of 12.26% is 60.9% above this benchmark. Historically, Martin Marietta Materials' own Operating Margin % has ranged from 16.59 to 23.66 over the past decade. While the company's 10-year median is 19.40 vs. the industry median of 7.62, Martin Marietta Materials has consistently been above the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Operating Margin % for a Building Materials company?
The median Operating Margin % among Building Materials companies is 7.62, based on 403 companies in the industry. Companies in the top quartile (top 25%) have a Operating Margin % significantly above this median, while those in the bottom quartile fall well below. However, Operating Margin % should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Martin Marietta Materials's current Operating Margin % of 12.26% is 60.9% above the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Operating Margin % mean?
A high Operating Margin % can signal that a stock is expensive relative to its fundamentals. Operating margin is the ratio of total operating income to net sales. View historical data on Martin Marietta Materials and its competitors. For the Building Materials industry, the median Operating Margin % is 7.62 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Martin Marietta Materials's current Operating Margin % is 12.26%, which is 37% below median its own 10-year median of 19.40. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Martin Marietta Materials stock overvalued right now?
Martin Marietta Materials (MIL:1MLM) has a current Operating Margin % of 12.26%. The stock's GF Value™ is €653.58, compared to a current price of €549.50 — trading 15.9% below its estimated fair value. The current Operating Margin % is 12.26%, which is 37% below median its 10-year median of 19.40 and 60.9% above the Building Materials industry median of 7.62. Martin Marietta Materials' overall GF Score™ is 92/100 with 3 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Operating Margin % calculated?
Operating Margin % is calculated from a company's financial statements. For Martin Marietta Materials (MIL:1MLM), the current Operating Margin % is 12.26% as of Mar. 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.
Is Martin Marietta Materials (MIL:1MLM) Overvalued in 2026?
Based on GuruFocus' analysis, Martin Marietta Materials stock appears to be undervalued.
The current stock price of €549.50 is trading 15.9% below its estimated GF Value™ of €653.58.
Key valuation signals for MIL:1MLM:
Operating Margin %: 12.26% (37% below median its 10-year median of 19.40)
GF Value™: €653.58 vs. price of €549.50 (15.9% below fair value)
Industry Position: 60.9% above the Building Materials median (#45 of 403)
No single metric tells the full story. See the MIL:1MLM stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Martin Marietta Materials is one of the United States' largest producer of construction aggregates (crushed stone, sand, and gravel). In 2024, Martin Marietta sold 191 million tons of aggregates. Martin Marietta's most important markets include Texas, North Carolina, Colorado, California, and Georgia, accounting for most of its sales. The company also uses its aggregates in its asphalt and ready-mixed concrete businesses. Martin's magnesia specialties business produces magnesia-based chemical products and dolomitic lime.
92GF Score
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