Duke Energy made about the same revenue and kept noticeably more of it. In the three months ended June 30, revenue rose 0.7% to $7.4 billion, while operating income climbed 12% to $2.0 billion and net income rose 11% to $1.1 billion.
That pushed operating margin to 27.6% from 24.8%. The surface reading is simple: Duke grew earnings without needing much more sales. The cash-flow math is less tidy, in the literal sense of the word.
Capital spending rose 28.2% from the comparable period, and the capex-to-revenue percentage increased 50.2%. Free-cash-flow margin fell 15.3 percentage points to negative 24.2%. Cash on hand did rise to $673 million from $344 million, but the latest period carried a much heavier investment load than the income statement suggests.
Some of the revenue increase came from regulated mechanisms and prices rather than a broad sales surge. Duke described the main contributors this way:
"The variance was driven primarily by: a $44 million increase in fuel-related revenues primarily due to higher natural gas costs passed through to customers, partially offset by lower natural gas retail sales volumes; a $35 million increase in retail revenue riders primarily due to the Distribution Capital Investment Rider, Base Transmission Rider, Ohio CEP Rider and Pipeline Modernization Mechanism Rider; a $33 million increase primarily due to higher pricing from the 2024 Duke Energy Kentucky electric rate case and the 2025 Duke Energy Kentucky natural gas rate case; and a $17 million increase in Bulk Power Marketing sales."
Duke Energy, 10-Q filed Aug. 4, 2026
That is a useful distinction. Revenue was nearly flat, but the pieces moving underneath it included fuel pass-throughs, rate cases, riders, and wholesale pricing. Natural gas costs also pushed expenses higher, including a $123 million increase in the cost of natural gas revenues.
The profit improvement had another important ingredient: recovery of infrastructure investment. Duke tied the increase in adjusted net income to that recovery, while also naming interest expense, operations and maintenance costs, and storm costs as offsets.
"Partially offset by: a $334 million increase in net income, after adjustment for non-cash items, primarily due to the recovery of infrastructure investments to reliably serve customers in our growing jurisdictions, partially offset by interest expense and operation and maintenance expense, including storm costs."
Duke Energy, 10-Q filed Aug. 4, 2026
The filing links infrastructure investment recovery to adjusted net income, while the figures show that a stronger profit period can still coincide with a weaker free-cash-flow margin.
Management says its territories are seeing economic development, population growth, and rising customer demand, creating substantial investment opportunities in coming years. The filing also identifies interest expense as an offset, making financing costs and the timing of regulatory recovery relevant context.
Duke's next report should provide the next comparable capex and free-cash-flow margin figures, showing whether this period's investment intensity was higher or lower than the latest run rate. For now, the three-month period's trade-off is plain: more earnings alongside more infrastructure investment, less free cash flow. Utilities do enjoy making the capital plan part of the product.
Source: Duke Energy 10-Q filed Aug. 4, 2026.