May CPI is expected to put US inflation back above 4%

The U.S. inflation report due Wednesday is expected to show a renewed acceleration in consumer prices, with Wall Street looking for a 0.5% monthly increase in the May consumer price index and a 4.2% annual rate, according to Dow Jones. Such a reading would take headline CPI above 4% for the first time since May 2023, adding pressure to markets already focused on oil-driven cost increases and their spread through the economy.

The Bureau of Labor Statistics is scheduled to release the May CPI report at 8:30 a.m. ET. In April, headline inflation ran at 3.8% from a year earlier, while core CPI stood at 2.8%.

The headline index measures a basket of goods and services purchased by consumers, including food, energy, housing, transport and medical care. The core measure excludes food and energy because those categories can move sharply month to month. Investors and policymakers track both: headline CPI captures the cost pressures households face, while core CPI can give a clearer signal of whether price gains are spreading into the broader economy.

Energy shock feeds into wider prices

The expected increase in the headline measure has been tied in large part to higher energy costs linked to the Iran war. Oil prices affect consumers directly through gasoline and utilities, and indirectly through freight, production and distribution costs. When those costs rise, companies can absorb them through margins or pass part of them on to customers.

Dow Jones expects core CPI to rise 0.3% in May, bringing the annual core rate to 2.9%. That would suggest price pressure beyond food and energy, though still below the expected headline rate.

Liz Ann Sonders, chief investment strategist at Charles Schwab, said the inflation concern now extends beyond oil. “It’s not just an oil story, it’s a money supply story, and it’s increasingly an AI story,” Sonders said. “So this is a broader inflation problem than just energy, meaning that we probably still have somewhat sticky inflation.”

Sonders said investor unease has been linked to inflation risk, and that a reading above expectations would likely be unwelcome for equities. Her comments reflect market sensitivity to whether the latest price shock remains concentrated in energy or becomes embedded across services and goods.

Policy debate centers on persistence

The Trump administration has argued that inflation should ease quickly once fighting in the Middle East calms. Sonders cautioned against assuming that oil prices would return to previous lows even under a quick resolution, citing disruption to production.

“Even if there would be a quick resolution to the war, you probably wouldn’t see oil prices come down to prior lows, because there’s been so much disruption to production,” she said. “That’s not something that a switch can just be turned back on.”

The report will arrive as households and financial markets assess whether higher fuel and transportation costs are becoming a broader inflation problem. A CPI print in line with Dow Jones estimates would confirm a step up from April’s annual rate and keep attention on how long the latest increase in prices lasts.

This story draws on original reporting from CNBC.