More than 2,000 members of the United Food & Commercial Workers Local 400 approved the strike earlier Monday, rejecting the company's contract offer, union officials said.
A Kroger spokesman said the company planned to close all 44 stores in the three states at midnight Monday; only its pharmacies will stay open.
"The proposal doesn't provide enough money to pay for our benefits," union president Jim Lowthers said. "They ought to be providing for the families that helped earn that money."
The union represents about 3,300 workers for the Cincinnati-based chain in 37 stores in West Virginia, five in Ohio and two in Kentucky. Kroger is West Virginia's fourth-largest employer, with about 5,100 employees statewide.
A 24-hour Kroger store in Charleston closed at 10 p.m. Monday, and about two dozen workers walked a picket line in the parking lot as passing motorists honked support. Picketing was planned for Kroger stores throughout the region.
"We ain't asking for all of it, just a fair shake," said Randy Atkins, who works in Charleston.
In Southern California, clerks at Safeway Inc.'s Vons struck late Saturday, at which point union employees were locked out at Kroger's Ralphs stores and at Albertsons groceries. Replacement workers have been, and are being, hired at the California companies, which control 60 percent of all grocery stores in the southern part of the state. More than 850 supermarkets and about 70,000 union workers at those stores are affected.
In Missouri, about 10,000 United Food & Commercial Workers members have been on strike at the St. Louis area's three largest chain grocers since last Tuesday. The 96 stores affected by the strike have hired temporary workers and cut back hours. The biggest sticking points are medical costs and pay raises.
Kroger proposed an 8 percent, or $9 million, increase for workers in West Virginia, Kentucky and Ohio, in what it pays into a health and welfare fund administered by a third party.
An independent actuary determined the fund needs an additional $29 million, Lowthers said.
The company's offer also included hourly pay raises this year and in 2005, along with lump-sum payments of $300-$500 in 2004 and 2006; and an increase in the number of full-time employees.
Pete Williams, president of Kroger's Mid-Atlantic region, wrote a letter to employees saying the company offers generous benefits compared to nonunion grocers such as Wal-Mart "who want our business and want your jobs."
Kroger made $542 million in profits through the end of August, down $27 million from 2002.