An updated version of the ZIPCODE data set is available. You can download the most recent version from SAS Maps Online.
The new ZIPCODE dataset, for April 2018, contains 41,072 observations and 21 variables. The package also includes the ZIPMIL and ZIPMISC datasets. These additional ZIP codes might not be included with the SASHELP.ZIPCODE file that ships with your version of SAS.
For information on "how to replace sashelp.zipcode", see these SAS Notes:
Source: zipcodedownload.com (April 2018)