Walmart, Target, Whole Foods, and others are dedicating shopping hours to high-risk customers during the coronavirus pandemic. Here's where to shop and when.

Walmart announced this week that it's shifting most stores to a schedule of 7 a.m. to 8:30 p.m. and introducing a new "senior shopping event."

"We know our older customers could be more vulnerable to the coronavirus and to better support them, Walmart is offering special shopping hours," Walmart US Chief Operating Officer Dacona Smith said. "From March 24 through April 28, Walmart stores will host an hour-long senior shopping event every Tuesday for customers aged 60 and older."

The event will start one hour before the store opens, which will be 6 a.m. for many locations. Pharmacies and vision centers will be open during the special shopping hour.

Dollar General is dedicating the first hour of operations every day in its more than 16,000 stores nationwide to senior customers, the company said this week.

"Dollar General wants to provide these at-risk customers with the ability to purchase the items they need and want at the beginning of each day to avoid busier and more crowded shopping periods," the company said in a news release. "Other customers are encouraged to plan their shopping trips around this window of time to allow the most susceptible customers in our communities the ability to shop during the first hour that stores are open."

Stop & Shop, a grocery chain with more than 400 stores, is opening stores early daily and dedicating the first 90 minutes of operation — from 6 a.m. to 7:30 a.m. — to people older than 60 and those with weakened immune systems, the company said.

"These hours are to help our more vulnerable customers shop in a less crowded environment, if they prefer," the company said.

Albertsons Companies is reserving two hours — 7 a.m. to 9 a.m. — on Tuesdays and Thursdays for vulnerable shoppers at its more than 2,200 stores nationwide.

These shoppers include senior citizens and other at-risk populations, such as pregnant women or those with compromised immune systems, the company said.

Albertsons owns more than 20 brands, including Safeway, Vons, Tom Thumb, and Randalls.

"We are asking our customers to respect these special hours for those who are most at risk in our communities, " said Albertsons CEO Vivek Sankaran. "We thank our customers in advance for their compassion and understanding toward their neighbors and friends, and in helping us maintain this temporary operations guideline."

Target CEO Brian Cornell announced this week that the company would reserve the first hour of shopping every Wednesday for "vulnerable guests, including the elderly and those with underlying health concerns."