US inflation heated up in August as tariffs started to drive up prices – although not enough to discourage bets that the Federal Reserve will start cutting interest rates next week.

The Consumer Price Index rose 2.9% in August compared to the previous year, speeding up from 2.7% in July, the Bureau of Labor Statistics said Thursday.

It jumped 0.4% from the previous month, above expectations of a 0.3% increase.

On a core basis, which excludes volatile food and energy prices, the CPI rose 3.1% over the past 12 months, remaining steady from the month before.

“The hot inflation print will not likely change the Fed’s plan to cut rates in September but it’s possible the Fed will hold in October if inflation expectations no longer look well-contained,” Jeffrey Roach, chief economist for LPL Financial, said in a note Thursday.

“In today’s numbers, we are seeing some impact from tariffs, especially with higher prices on cars and clothes.”

The Dow soared more than 600 points in midday trading, breaking through 46,000 for the first time. The S&P 500 and Nasdaq also continued on their sizzling pace, both rising nearly 1% to hit new highs.

The CPI index for new vehicles rose 0.3% in August. Used cars and trucks – which typically rise in tandem, since higher prices on new cars will spike demand for more affordable options – rose 1% in August, up 6% over the past 12 months.

Supply chain issues during the pandemic caused a shortage of new cars in the US, and mounting tariff anxiety has further raised demand for used vehicles.

Apparel – another highly tariff-sensitive category – rose 0.5% in August over the month, heating up from a 0.1% pace in July.

“There are some industries holding onto their pre-tariff prices. Autos and apparel feel it more so because so much of it is shipped,” Ken Mahoney, CEO at Mahoney Asset Management, told The Post.

“There is most likely a certain point of tolerance they can absorb, and they are no longer able to absorb them and pass along to consumers.”

But it would have taken a wild inflation report to squash rate cut hopes after Fed Chairman Jerome Powell signaled last month that central bankers are more concerned with weakness in the labor market than inflation fears.

Following the consumer price report, traders still bet on 100% odds that the Fed will slash rates by at least a quarter point at its meeting next week, according to CME FedWatch.

Producer price data released Wednesday showed wholesale inflation unexpectedly fell 0.1% in August from the previous month as businesses continued to eat the bulk of tariff costs.

Meanwhile, the Labor Department on Thursday reported a surprise increase in weekly unemployment filings to a seasonally adjusted 263,000 for the week ended Sept. 6 – the highest level in nearly four years.

Earlier this week, jobs growth was revised downward by a whopping 911,000 in the biggest downward adjustment since 2000.

“More so than anything, the number that sticks out today is jobless claims coming in higher than expected, along with the very poor jobs report that creates a certainty that we get a rate cut next week,” Mahoney told The Post.

The Dow Jones Industrial Average jumped 497 points, or 1.1%, by approximately 10:15 a.m. ET, while the S&P 500 and Nasdaq rose 0.6% and 0.4%, respectively.

Thursday’s CPI data showed the index for shelter rose 0.4% in August from the previous month, and was the largest factor in the overall monthly increase, according to the Labor Department. It’s up 3.6% over the past 12 months.

Food jumped 0.5% from the previous month. The food at home index rose 0.6% while the food away from home index increased 0.3%.

Energy jumped 0.7%, with gasoline increasing 1.9% over the month.

Plane ticket prices have soared as travel demand has come roaring back after the pandemic. The index for airline fares jumped 5.9% over the month, after rising 4% in July.

The indexes for medical care services, recreation and communication were among the few major categories that declined in August, falling 0.2%, 0.1% and 0.1% respectively – though medical care is up 4.2% over the past year.