The Labor Department said its consumer price index rose 0.1 percent in July, slowing from a 0.3 percent gain in June and the smallest monthly increase since April.
Food prices rose 0.2 percent. Energy prices were up 0.1 percent, led by a 0.9 percent rise in gasoline prices that offset declines in other components, including fuel oil.
Excluding food and energy, which tend to be volatile month on month, core CPI also rose 0.1 percent, down from 0.2 percent in June.
But on a 12-month basis, consumer prices were up 0.2 percent, building on a gain since April. Core CPI year-on-year was roughly steady at 1.8 percent.
The Federal Reserve's target for price stability is 2.0 percent inflation over the longer term. The central bank's preferred inflation measure, the personal consumption expenditures price index, increased 0.3 percent in June compared with a year ago, and excluding food and energy, was up 1.3 percent.