If you've sworn off retail store shopping because the items you want never seem to be in stock, Wal-Mart says it's now safe to come back. Though it can't guarantee that all of its shelves will be fully stocked at all times, the mega-retailer says stock-outs at its stores are about to become far less common now that it's using RFID technology for inventory tracking at more than 500 stores.

Ten months after it began receiving RFID-tagged cases and pallets from its top 100 suppliers, Wal-Mart says it's already seen a 16-percent reduction in out-of-stocks at stores that use the technology. In a study released in October, Wal-Mart also noted that replenishment rates were three times higher at the RFID-equipped stores than at their RFID-free counterparts, and that the number of manually placed orders at the RFID-equipped stores had dropped by 10 percent. For the study, Wal-Mart tracked specific items on a daily basis for 29 weeks at 24 stores—12 pilot locations using RFID and 12 that are not outfitted with the technology. (Wal-Mart, however, did not disclose how the reduction in out-of-stocks affected its revenue.)

Wal-Mart has installed RFID equipment at a feverish pace this year to meet its goal of equipping 500 additional store sites and five distribution centers by the end of October. The RFID push has been on at its DCs as well. In January, 200 more suppliers will join the existing base of 130 suppliers in shipping RFID-tagged cases and pallets. By the end of next year, more than 1,000 Wal-Mart stores, clubs and DCs will be using the technology.