March 6 (Bloomberg) — Boeing Co., the world's largest planemaker, will freeze pensions for 68,000 nonunion employees and executives, shifting benefit payments to a 401(k)-style plan, as it works to cut costs.

The change will take effect Jan. 1, 2016, the Chicago-based company said today in a statement. Employees will be able to keep any accruals already made to their pensions provided on Boeing's defined benefit plan as the company shifts payments to a defined contribution plan. Employees hired since 2009 and new members of 28 unions are already on this plan.

Boeing is curbing pension expenses that, at $3.45 billion over the last 12 months, are the third-highest among large U.S. corporations, according to data compiled by Bloomberg. General Electric Co.'s $5.05 billion expense was the largest, followed by Exxon Mobil Corp.'s $3.73 billion.