Tepid sales at many retail chains in June reinforced concerns that the U.S. consumer is pulling back on spending amid lingering economic uncertainty.

Issaquah-based Costco reported a gain below Wall Street estimates Thursday, while Target and Macy's also fell short.

But concerns about a slowdown in consumer spending were not reflected in the results of upscale retailers such as Nordstrom.

Seattle-based Nordstrom said its sales at stores open more than a year rose a better-than-expected 8.1 percent, boosted by strong demand for handbags, jewelry and shoes.

Zumiez, a teen-oriented clothing chain based in Everett, posted robust growth of 8.2 percent, narrowly missing analysts' upbeat prediction for an 8.4 percent rise.

Same-store sales at the more than 20 companies tracked by Retail Metrics rose 0.3 percent, compared with the 1 percent average estimate of analysts surveyed by the research firm. The results follow a 7.2 percent increase last year.

Consumers have been spooked by the unemployment rate staying above 8 percent, sending many to discount chains such as TJX, which posted a 7 percent sales gain. TJX, which owns discount stores T.J. Maxx and Marshalls, beat analysts' estimates of a 3.7 percent increase.

At the same time, luxury consumers have continued to spend with the stock market still up for the year.

"The high-end consumer has faired particularly well throughout this recovery," said Ken Perkins, president of Retail Metrics. "On the low end, a lot of middle-income consumers have traded down."

Costco reported a 3 percent gain in sales at stores open more than a year, below the 3.7 percent rise analysts expected.

Excluding the impact of gasoline prices and foreign currencies, Costco said revenue from stores open at least a year climbed 5 percent.

Same-store sales at Limited Brands, parent to Victoria's Secret, gained 7 percent, beating the average estimate of 2.6 percent.

Sales at Target rose 2.1 percent, falling short of the average projection for a 2.8 percent gain from analysts surveyed by Retail Metrics. Macy's, the second-biggest U.S. department-store chain, posted a 1.2 percent increase in same-store sales, missing the 2.3 percent estimate.

Material from Bloomberg News and Seattle Times business reporter Amy Martinez is included.