How long does a DWI show on a background check?

If you were charged criminally for the offense - and it occurred after your 18th birthday it will appear on your criminal background check. However in most states you may be eligible to have it expunged from your CRIMINAL record.

If you are referring to your DRIVERS record - it will ALWAYS appear. They are not like points against your license which disappear after a certain length of time. Your driving record is a lifelong compilation of all your violations. They are not subject to expungement.