PURCHASE, N.Y. – MasterCard Inc. on Tuesday said its first-quarter profit jumped 24 percent, with more shoppers feeling comfortable enough about the economy and their jobs to reach for the plastic again.

The payment processor earned $455 million, or $3.46 per share in the first three months of the year, compared with $367 million, or $2.81 per share, in the year-ago period.

Revenue climbed 13 percent to $1.31 billion, from $1.16 billion last year. MasterCard said about 5 percent of that gain came from raising the prices it charges to merchants for processing transactions.

The results easily topped the $3.14 per share and $1.27 billion revenue expected, on average, by analysts polled by Thomson Reuters.

The healthier profits reflect 5 percent growth in the number of transactions processed, and an 11 percent increase in MasterCard’s international volume.

The use of credit cards in the U.S. remained sluggish, dropping 3 percent. That was a far smaller decline than the double-digit drops seen for most of 2009, and Chief Financial Officer Martina Hund-Mejean said that credit use actually edged slightly higher in March and April.

But debit card used surged everywhere. MasterCard said total debit volume using cards that draw money from bank accounts rose 18 percent worldwide, 7 percent in the U.S..

That means that even as the economy starts to recover and consumer confidence is growing, U.S. shoppers are still hesitant to take on more debt.

In the U.S., MasterCard debit use pulled even with credit use in the first quarter. A year ago, credit topped debit use by more than 16 percent.