Energy Prices Put US Inflation Above 4% for First Time in Three Years
Energy accounted for about 60% of May's monthly CPI increase, pushing the annual rate to 4.2% and putting the Fed's September meeting back in play.
US inflation climbed above 4% for the first time in three years in May, with the Consumer Price Index rising 0.5% from April and 4.2% from a year earlier, according to the Bureau of Labor Statistics. The annual rate matched economists' expectations but marked the fastest reading since April 2023 and an acceleration from the 3.8% rate recorded in April.2
Energy did the heavy lifting. The BLS reported energy prices jumped 3.9% on the month and 23.5% from a year ago, with energy accounting for roughly 60% of the monthly increase in consumer prices — a share that ties the inflation print directly to the oil rally following the outbreak of hostilities involving Iran.2
The core reading is where the print gets uncomfortable. Core CPI, which strips out food and energy, rose 0.2% on the month and 2.9% annually. Steady, not alarming — but not the number a central bank wants to see when headline is accelerating and the question of whether the energy shock leaks into wages and services remains open.2
Food prices increased 0.2% and shelter costs rose 0.3%, both quieter than the headline suggests. Strip out the energy contribution and May's CPI looks closer to the trend that prevailed before the Iran war.2
Markets have been pricing the other side. At Friday's close (2026-07-17), Brent crude topped $100 and futures traders assigned an 81% probability to a September rate hike, according to CME FedWatch data. Gold fell that session as the oil rally hardened rate expectations.3
The war premium cooled after June. The Economist noted on 2026-05-17 that oil was about 25% down from its peak in June, with food prices more than 10% down. That disinflationary move sits directly against the May print, and it is why one hot CPI number has not settled the debate.1
The sequencing matters. The May data capture a war-driven energy shock that has since partly unwound in crude. If the Fed hikes in September into a falling oil price, it risks tightening into a fading impulse. If it holds, it risks being seen as tolerant of 4%-plus headline prints. Both outcomes remain live.3,1
The mismatch between headline and underlying inflation is widest in the Anglosphere, ranging from 3.8% to 4.6% across America, Britain, Canada and New Zealand, with the euro zone averaging 2.4%, the Economist found. The UK is already showing pass-through effects: shop price inflation hit a two-year high and is set to climb through the autumn as energy and commodity costs filter into consumer prices, the British Retail Consortium warned.1,4
The demand-side backdrop complicates the picture. Pandemic-era stimulus worth 10% of global GDP caused overheating, the Economist argued, which is why the underlying rate is likely to stay higher than the pre-pandemic norm even as current disruptions fade. That is the argument against reading May as a one-off.1
For energy traders the CPI print is not the trade itself. The trade is what the Fed does with it, and what that does to the dollar and to demand. The dollar index sat at 99.09 as of 2026-09-12, with EUR/USD at 1.16 — a rate that keeps imported energy costs elevated for European buyers.2,3
The 81% September hike probability from CME FedWatch data is the number to track through the next inflation release. If it holds, the tightening impulse becomes real for demand and for the front of the crude curve. If it fades as crude stays below its June peak, May's 4.2% print will look like a war artefact — and the Fed will have been right to wait.3,1