walmart shopper
REUTERS/ Kevork Djansezian
Wal-Mart's prices in stores differ from those listed on its website.
Wal-Mart is charging more for school supplies online than in its stores.
Bloomberg Intelligence analysts purchased 31 identical items to compare prices and in three out of four surveys, prices online exceeded those in stores, Businessweek reports.
The difference in costs was slight, with online pricing adding 1.8% at most to a $118 ticket.
This isn't the first time that Wal-Mart has been discovered using different pricing strategies online and in stores.
Consumer advocate Clark Howard reported in July that a lego set, which he intended to buy for his son, cost 35% more in a Wal-Mart store than on the retailer's website.
When he asked a Wal-Mart employee about the discrepancy, he was told that the store doesn't match its online prices. 
"So I had to buy it on Walmart.com and do the free pickup option in the store to get the lower price," Howard wrote. "My son and I stood there and watched as a different employee came a few minutes later, picked the item up off the shelf, and brought it back to the holding spot for pickup."
But there was a catch to Howard's clever maneuver. 
"Unfortunately, I didn't get the confirmation that it was available for pickup until the next day! So I had to go back the next day to pick it up!! That's *not* good customer service," he wrote. 
Wal-Mart states on its website that store managers are not required to match prices online — or those listed at other Wal-Mart stores — because the company is not competitive with itself. 
"Prices may vary from store to store because each store is required to manage its own inventory," the website states. "Therefore, a manager may lower a price to clear out an overstock item, to reward customers with an in-store sale, or to compete with local merchants. It is not our policy to price match our own stores or our online service since we are not in competition with ourselves.".