When you imported, Access must have set the field to numeric.
Add a new Zipcode field to your table, and make it Text.
Use an update query to update the new field to Right$("00000" & OldZipField,
5)
Once you've checked that the new field is correct, you can delete the old
field.

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Doug Steele, Microsoft Access MVP
http://I.Am/DougSteele
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> I imported a table from excel and now the zip code column will not show a "0"
> in front of certain postal codes (i.e. the zip code for 02116, shows 2116).
> How do I use the input mask to properly set the zip code format?