U.S. freight spend is accelerating. The expenditures component of the Cass Freight Index, which measures the total amount spent on freight, rose 20.4 percent year over year in September 2026 to 3.970 (Cass Transportation Index Report, September 2026). In August the gain was 19 percent; before that, the year-to-date pace was 5.5 percent (Cass, September 2026).
Budgets built on last year's freight run-rate are now out of date.
What the 20 Percent Actually Measures
The headline needs careful reading. A 20 percent rise in expenditures is not a 20 percent rise in rates. Cass attributes the acceleration to three drivers working together: higher shipments, higher rates and higher fuel surcharges (Cass, September 2026). The index also reflects freight paid through Cass's own client base of hundreds of large shippers (Cass Freight Index methodology), so your exposure will differ by mode, lane and contract mix. Treat it as a direction-of-travel signal for your own spend, not a number to paste into the budget.
Each driver calls for a different response, which is why the decomposition matters:
| Driver | September 2026 signal | What it means for the budget |
|---|---|---|
| Volume | Shipments index 1.062, up 1.9% y/y and 2.3% m/m; the second straight y/y gain after a 3.5-year downturn, the longest on record by this measure (Cass) | More loads moving. Part of the spend increase is the business growing, not cost inflation |
| Rate | Truckload Linehaul Index 154.8, up 10.1% y/y and 0.6% m/m; on pace for a 7% increase in 2026 after falling 10% in 2023 and 3.4% in 2024, then rising 1.8% in 2025 (Cass) | Cost per load is rising, and the larger contract market is still adjusting upward |
| Fuel | Named by Cass as a driver of the expenditures acceleration; Cass also cites rising oil prices as a limiting factor for demand (Cass) | Surcharge tables pass changes through quickly. Check how yours are indexed |
Why This Is an End-to-End Supply Chain Issue
Freight is where upstream decisions show up as cost. Cass links the volume recovery to modest retail and industrial growth and to "some inventory restocking as container imports surge" (Cass, September 2026). That puts transportation in the middle of a chain that runs from demand planning through inventory placement to final delivery.
The inventory side of that chain is visible in public data. The U.S. Census Bureau's merchant wholesalers inventories-to-sales ratio was 1.18 in August 2026, down from 1.28 in August 2025 (U.S. Census Bureau via FRED, WHLSLRIRSA). Leaner stock relative to sales means less buffer and, when restocking begins, more freight. Where that inventory is positioned decides how many miles the freight travels and how often it has to be expedited.
A freight budget is a downstream reflection of inventory, network and service decisions made months earlier.
The Contract Market Is Still Catching Up
Cass notes that the September rate increase was slower than the 0.9 percent year-to-date monthly average, partly because spot rates eased and few contracts were bid at this time of year. But "the much larger contract market is still adjusting higher" (Cass, September 2026). Shippers whose contracts renew in the next bid cycle should expect the reset to reach them.
Intermodal is the other side of the ledger. ACT Research, which writes the Cass report, estimates 19.3 million North American intermodal loads in 2026, above the 2018 record of 18.9 million, and says the intermodal cost advantage is above average (Cass, September 2026). ACT's own open question is whether the railroads can execute at that demand level (Cass, September 2026).
Questions Every Distribution Leader Should Be Able to Answer
- How much of your freight increase is volume, how much is rate and how much is fuel? If you cannot split it, you cannot tell growth from inflation.
- When do your largest truckload contracts reprice? The contract market is still adjusting upward (Cass).
- Which lanes could shift to intermodal without breaking service commitments?
- How much expedited freight did you pay for last quarter, and what inventory gap caused it?
- Does your freight budget move when your inventory plan moves? If they are set by separate teams on separate calendars, they will drift apart.
Five Moves Before the Next Budget Cycle
1. Re-baseline the freight budget. Rebuild it from expected volume, lane-level rates and a fuel assumption, rather than inflating last year's total. Cass puts the full-year expenditures gain on track for 12 percent in 2026 (Cass, September 2026); your number should come from your own lanes.
2. Prepare for bid season now. Know your lane volumes, service requirements and incumbent performance before carriers price the next contract round.
3. Test mode shift. With intermodal volumes forecast at a record and its cost advantage above average (ACT Research in Cass), model which lanes can move without hurting service levels.
4. Link freight to inventory placement. Stock in the wrong place can be paid for twice: once to move it, and again to rebalance it or expedite a replacement. Review placement before restocking volumes peak.
5. Audit fuel surcharge mechanics. Confirm the index, base price and step table in each contract, so fuel pass-through is predictable rather than a surprise on the invoice.
The Bottom Line
Two months of growth do not make a trend, and Cass says so itself (Cass, September 2026). But freight spend is rising on volume, rate and fuel at the same time, and the contract market has not finished resetting. Leaders who connect the freight budget to inventory and network decisions will manage the increase; those who treat it as a line item will simply absorb it.
Plan the freight. Don't just pay it.
