Common AAMVA barcode format errors to look for

AAMVA barcode errors in vendor cards tend to cluster in a few specific fields, and knowing which ones to check tells you what to look for when you run a decoded barcode through a verification app.

Jurisdiction Code

The jurisdiction code in the barcode header identifies the issuing state. I've seen this field encoded with the correct state abbreviation in the visible data but the wrong numeric jurisdiction code in the underlying encoding. The discrepancy only shows up when you use an app that displays the raw header fields rather than just the decoded text. App-level validation that cross-references the jurisdiction code against the state name field will flag this inconsistency; apps that just display decoded fields won't.

Date Encoding

AAMVA encodes dates in MMDDYYYY format without separators. A date of birth of January 15, 1998 encodes as 01151998. I've seen vendor cards where the date format is correct in one field and wrong in another — for example, the date of birth encoded correctly but the expiration date formatted as YYYY-MM-DD instead. This typically decodes as a garbled date rather than a completely missing field, so it shows up as an obviously wrong value rather than a blank.

Missing Optional Fields

AAMVA defines mandatory fields and optional fields. Most states use several of the optional fields — hair color, eye color, organ donor status. Vendor cards sometimes omit optional fields entirely or populate them with the default value rather than the state-specific correct value. An app that validates optional field presence against a state profile will flag these; a generic decoder won't.

The practical check: when you decode a card, compare the field list against what a genuine card from that state should contain. If fields that should be present are missing or show default values, that's an encoding gap. Most of these don't cause failures in casual use but they'll show up under any systematic verification.