The minimum wage in Missouri will rise 10 cents an hour on Jan. 1.

Since 2008, state law has had a built-in cost-of-living adjustment. That will push the wage floor up to $7.35 from $7.25, putting the state rate 10 cents higher than the federal mandate.

The Missouri Department of Labor and Industrial Relations said the state’s increase will add about $200 a year in wages for a full-time minimum-wage worker.

About 1.4 million workers are expected to benefit.

Employees of a retail or service business with gross annual sales or business of less than $500,000 are not covered by the law.

Missouri is among 10 states nationally that have annual cost-of-living assessments built into their minimum wage laws. The others are Arizona, Colorado, Florida, Montana, Nevada, Ohio, Oregon, Vermont and Washington.

Missouri will be among 18 states with minimums that are higher than the federal rate of $7.25, which translates into annual income of a little more than $15,000 for a full-time worker.

For most workers in Kansas, the federal rate will continue to apply. There is a Kansas exception for tipped workers, which sets the minimum at $2.13 an hour.

Proponents of raising the state floor had tried but failed to put a measure on the Nov. 6 ballot. That proposal would have raised the state base to $8.50 an hour.

Business interests generally oppose minimum wage increases, saying they hurt entry-level workers they are supposed to help. The Employment Policies Institute, for example, says higher minimums do nothing to reduce poverty or increase entry-level employment, especially for teens.

Opponents also say the minimum wage sets a base rate for other wages, so when the minimum rises, other pay rates go up, which inflates total payroll costs and causes layoffs.

Advocates for raising the minimum wage say increases are necessary because today’s minimum wage has 30 percent less buying power than it did in 1968. If today’s minimum wage had kept pace with the inflation rate, it now would be more than $10 an hour.