Mueller Industries, Inc. (MLI) Income Statement

The sequence from 4.2% to 19.3%, 25.5% and 31.6% over the last four quarters suggests genuine demand broadening into commercial, industrial and electrical end-markets rather than a single-quarter artifact, since the acceleration spans three consecutive periods. However, because a rising copper price inflates the revenue line mechanically under cost pass-through, the 31.6% figure may overstate underlying unit growth, and durability depends on whether construction-related volumes hold once input inflation normalizes. Investors should treat the growth rate as an upper bound on organic expansion until volume and price are disaggregated.

A 450 basis point sequential compression while the top line grew by double digits implies the metal spread narrowed, pointing to either inventory sold from higher-cost LIFO layers or competitive limits on passing through spot copper increases. The 25.5% level is still above the 21.6% trough in 2025Q4, but it sits well below the 30-31% prints of 2025Q2 and 2026Q1, indicating current profitability may be reverting from an unusually favorable spread rather than establishing a new plateau. Since gross margin drives essentially all of the operating income swing here, the direction of this line is the single most important variable to monitor.

SG&A has stayed in a narrow $52.7-67.8 million band across all ten quarters while revenue grew from under $1.0 billion to roughly $1.4 billion, so the fixed-ish cost structure is converting top-line growth into operating income at a favorable rate. This explains why operating margin reached 26.2% in 2026Q1 on 19.3% revenue growth: gross profit scaled while selling and administrative costs did not track it proportionally. The offsetting read is that the same leverage works in reverse, so any revenue deceleration would compress operating margin faster than gross margin alone would imply.

That quarter combined a 30.0% gross margin with an unchanged SG&A base of $66.8 million, producing $312.2 million of operating income on only $1.2 billion of revenue — an outcome that appears to reflect a wide metal spread meeting fully absorbed overhead. The lasting implication is that 2026 benchmarks and consensus may be anchored to a spread environment that has since narrowed, as 2026Q2 and 2026Q3 operating income slipped to $310.0 million and $281.6 million despite higher revenue. Whether the Q1 peak proves cyclical or structural hinges on scrap availability and copper price stability, neither of which is visible in the income statement itself.