DALLAS — AT&T Inc. said it would lay off about 4,650 workers, trimming the managerial ranks in its fading home-phone business after more than $100 billion in acquisitions.

The decision covers about 1.5 percent of the workforce, San Antonio-based AT&T said yesterday in a regulatory filing. The dismissals at the largest U.S. phone company are in addition to the 10,000 announced with the $86 billion purchase of BellSouth Corp. in December 2006, spokesman Walt Sharp said.

Most of the reductions apply to the local-phone business, Sharp said. That unit lost 1.6 million residential lines last year as customers switched to cable and wireless phone service. AT&T has sought to reduce overlap in its operations since buying BellSouth and the former AT&T Corp., with plans to slash annual costs by about $7 billion by 2009.

Economists predicted this month that the U.S. economy won't grow in the first half of the year, the weakest performance since the 2001 recession, as consumers grapple with falling home prices and increasing energy costs.

AT&T plans to book a pretax cost of about $374 million for the job cuts in the first quarter. Before the announcement, analysts on average predicted AT&T would report net income of $3.95 billion for the period. The phone company had about 310,000 employees as of Jan. 31.

The cuts will occur in all parts of the U.S., Sharp said.