The company said on Friday that the reductions have been planned for some time and have nothing to do with battery problems in its 787 jetliners. It didn't say how many workers are affected.
Boeing assembles 787s in its North Charleston plant, as well as at a larger facility in Everett, Wash.
Boeing Co. spokeswoman Candy Eslinger said the North Charleston plant employs more than 6,100 people. That includes regular employees and contract workers at the 787 assembly plant as well as another facility that makes the plane's tail section. She said none of the regular Boeing workers are affected.
She said contract employees have had the chance to apply for permanent Boeing jobs in recent months. It's standard practice in the industry to use contract workers when production at a plant is being ramped up, she said.
The 787 is Boeing's newest plane, and the North Charleston plant delivered its first one in October. The plane is built in sections all over the world - including the tail in North Charleston - and then assembled there and in Everett. Boeing has said it aims to build about three planes a month in North Charleston by the end of the year, out of 10 per month total.
The 787 has been grounded since Jan. 16 because of a smoldering and burning batteries. Deliveries are halted. Boeing has said it intends to keep building the planes at the same pace, though.
Boeing employs more than 173,000 people worldwide. Its defense business has been shrinking, while there has been some growth in its commercial airplanes. The company said on Friday that it will hire roughly 8,000 to 10,000 people this year, but expects overall employment to be flat.
The reductions were first reported late Thursday by The Wall Street Journal.
Boeing Co. shares rose 25 cents to $77.15 in morning trading.
Josh Freed in Minneapolis contributed to this story.