New York ? The start of the back-to-school shopping season was a disappointment for major retailers, giving the industry a third straight month of listless sales. Higher gasoline prices contributed to the poor showing in August.

Wal-Mart, Limited Brands, Talbots Inc. and Costco Wholesale Corp. were among the companies issuing reports of sluggish sales Thursday.

Hannah Poole, left, and Amanda Schlitzer shop at an American Eagle store in Plymouth Meeting, Pa. The looked at jeans Wednesday. The start of the back-to-school shopping season was a disappointment for major retailers. However, American Eagle Outfitters Inc., which analysts say has been stealing market share from other teen retailers this past season, reported a 23.9 percent increase in same-store sales.

“Overall, this doesn’t look so good,” said Ken Perkins, president and research analyst at RetailMetrics LLC, a Boston-based independent research company. “There are a number of different factors that are coming together to dampen consumer spending.”

Retailers found low-to-middle-income shoppers were more frugal in response to higher gas prices and also higher grocery bills. Sales figures also were affected by technical factors and a late Labor Day weekend, which will come a week later than a year ago and will push sales into the September reporting period. In addition, the 2003 results were boosted by the government’s one-time child care tax credits.

But overall, sales were hurt by consumers’ concerns about money and jobs. On Tuesday, the Conference Board reported a larger than expected decline in consumer confidence.

Wal-Mart, the world’s largest retailer, posted a slim 0.5 percent increase in same-store sales, missing Wall Street forecasts for a 1.5 percent gain.

Same-store sales are sales at stores open at least a year and are considered the best indicator of a retailers’ health. Total sales at Wal-Mart rose 8.8 percent.

Costco reported a 4 percent gain in same-store sales, missing Wall Street’s 7.3 percent forecast. Total sales were up 7 percent.

Mall-based apparel stores also struggled. Talbots had a 4.6 percent drop in same-store sales, a slightly better result than the 5.3 percent drop Wall Street forecast. Total sales fell 1 percent.

But high-end department stores, whose business is less vulnerable to the rising energy prices, again beat expectations. Nordstrom Inc. had a 7.2 percent gain in same-store sales, surpassing Wall Street’s 4.7 percent estimates. Total sales rose 8.2 percent.