1. If the file does not already have a .TXT extension, change the extension to .TXT:
    1. Locate the file with leading zeroes in Windows Explorer and right-click it. It may be necessary to change your folder options to display file extensions.
    2. Select Rename from the menu. Note: Do not open the CSV file in Excel before renaming it. Otherwise, you will lose the leading and trailing zeroes and will not be able to retrieve them.
    3. Change the extension from .CSV to .TXT 
  2. Open Excel.
  3. Select File, Open from the menu bar.
  4. Change Files of type to All Files.
  5. Browse to the .TXT file.
  6. Highlight the file and click Open.
  7. Select the Delimited option and click Next. 
  8. Unmark the Tab checkbox, mark the Comma checkbox, and click Next. 
  9. Highlight the first column that has data containing leading zeroes and select Text as the Column data format. 
  10. Repeat step 8 for each column that has data containing leading zeroes (in the example, the ZIP Code column). 
  11. Click Finish. The file opens in Excel and retains the leading zeroes.