WASHINGTON – Employers advertised more jobs in September than at any other point in the past three years. The increase suggests hiring could pick up in the next few months.

Competition for jobs is fierce. And many employers aren’t rushing to fill some because they are worried about the strength of the economy.

Still, most economists say the increase in openings is a reassuring sign.

Nearly 3.4 million jobs were posted in September, the Labor Department said Tuesday. That’s the most since August 2008, one month before the financial crisis intensified.

“Business confidence appears intact,” said Alan Levenson, an economist at T. Rowe Price, “confirming … that job growth is going to continue.”

Job openings have rebounded from a decade low of 2.1 million in July 2009. But they are well below the 4.4 million advertised in December 2007, when the recession began.

Almost four years later, roughly 14 million people are unemployed. An average 4.2 unemployed workers were competing for each opening in September. That’s slightly better than August, but it is still more than twice the 2-to-1 ratio that economists say is healthy.

More openings do not necessarily mean more jobs. Even though job openings rose 22 percent in the past year, hiring has increased only 10 percent, the Labor Department’s report shows.

Education and health care providers have boosted their openings 21 percent in the past year. Yet hiring in those fields has dropped. Retail job openings have soared more than 40 percent in the past year, but hiring has been flat.

U.S. employers remain extremely cautious. Modest growth during the summer helped calm recession fears. But the growth came after consumers spent more while earning less, a trend that economists fear can’t be sustained.

And the economy remains vulnerable to shocks. Europe’s debt crisis could intensify and throw the continent into a recession, which would slow U.S. exports and reduce growth. U.S. lawmakers are expected to sharply cut federal spending, which could mean fewer government jobs and less consumer spending.

“When you have a lot of uncertainty, an employer may choose to postpone their hiring plans,” said Henry Mo, an economist at Credit Suisse.

The economy added 158,000 net jobs in September. Hiring slowed a bit in October, as employers added only 80,000 jobs, the fewest in four months. Even so, the unemployment rate dipped in October to a six-month low of 9 percent, from 9.1 percent, because more people said they found jobs.