Top Codes

• Walmart places codes that deal with identification of the store (ST#), the cashier operator (OP#), terminal or aisle number (TE#) and transaction number (TR#). Although most of the time this information only helps the store track transactions, if you leave a bag or your wallet at checkout, knowing what aisle or cashier might prove helpful in finding it. The TC# the bottom of the receipt contains the Walmart transaction code.
  
  

Bar Codes

• Bar codes contain bars for scanners and numbers for people to read.Medioimages/Photodisc/Photodisc/Getty Images
  
  Stores began using the Universal Product Code (UPC) to help computerize and manage inventory and sales approximately 25 years ago, according to Northern Kentucky University Associate Professor Deepak Khazanchi and Assistant Professor Fred Beasley. A variety of bar codes exists for different industries with different numbers of digits. In the United States, merchandise bar codes scanned at point-of-sale must comply with the EAN/UPC symbols, according to GS1 US. Walmart uses a UPC code containing 12 digits.
  
  

UPC

• The numbers on the UPC code usually match the UPC code of the product you purchased, with the first 6 digits identifying the manufacturer and the next five digits identifying the product. Sometimes an item may not have a UPC code, or special handling may require the cashier to enter a code manually. The twelfth number helps validate the code so that it belongs to only one product. The words or letters before the numbers tell you the product, and the numbers to the right contain the price. These codes provide necessary verification for purchases, including many rebates, or for return or exchange purposes. Although the codes should help prevent people from swapping bar codes from cheaper to more expensive items, cashiers at Walmart and other stores often fail to verify if the item scanned matches the code, according to editor Evan Schuman.
  
  

Tax

• The tax codes on your receipt depend on your location. Some states either do not tax food and some other items or tax them at a lower rate. Therefore, your receipt may show simply a total tax or it may contain two or more tax percentage rates and the amount charged for each.
  
  

Payment

• The final codes depend on your method of payment. When using a credit or debit card, the numbers after "account" show the last four digits of the card. The codes following that contain the identification numbers for card approval, transaction identification and a validation code.