Walmart Inc. outlined average wages for its store workers and efforts to improve benefits in a social responsibility report, part of the retailer’s long-running efforts to rebut criticism of its pay and bolster its competitive position in a tight labor market.

Walmart’s U.S. store managers earn an average of $175,000 a year while full-time hourly workers make an average of at least $25,000, or $14.26 an hour, the company disclosed Wednesday.

Pressure...