Hawaiian Airlines said today its passenger traffic rose 3.4 percent in September but that its fuel costs for the third quarter likely ended higher than it previously forecast.

The state’s largest carrier said it transported 913,488 passengers last month compared with 883,315 in the year-earlier period. Its load factor, or the percentage of seats filled, rose 1.6 percentage points to 86.6 percent from 85.0 percent.

Revenue passenger miles, or one paying passenger transported one mile, jumped 6.3 percent to 1.37 million from 1.29 million. Available seat miles, or one seat transported one mile, increased 4.3 pecent to 1.58 million from 1.51 million.

The airline, which is scheduled to announce its third-quarter earnings on Oct. 19, revised upward its economic fuel cost per gallon to a range of $1.65 to $1.75 from its original guidance of $1.55 to $1.65. Hawaiian also said the gallons of jet fuel it consumed last quarter is now expected to have risen 3 percent to 4 percent from the year-earlier period. That is narrower than the previous guidance of a 3 percent to 5 percent increase.