If you currently do not use your TWIC with a card reader, then you do not need to get a replacement right away-you will be able to get one later.If you confirm that your TWIC has this problem (and is on the TSA list), then you have two options:.What do I do if my card has a truncated FASC-N?.The TWICs that have this problem can be identified by the 8-digit Agency Serial Number (ASN) that is printed on the back of the TWIC.The ASN is on the bottom left side of the back of the card (on the same line as the numbers ‘7099′ which appear on the bottom right.) Click here, to see if the ASN on your TWIC matches a number on the TSA list.If it does, then your card has a truncated FASC-N and you may need to obtain a replacement depending on how you use your card.How can I determine if my TWIC is affected by this issue?.The system error causing the FASC-N to be truncated was corrected on Apand TWIC issued before this date (April 5, 2011) could potentially have this issue and as a result, TWIC readers could have problems reading these cards.TWICs issued after that date do not have truncated FASC-Ns.What time frame did this problem occur?.

TSA estimates that the integrated circuit chips (ICCs) on approximately 26,000 previously issued TWICs were improperly encoded and may not work with TWIC readers.

Click here to access the TSA notification bulletin on this issue.

Every TWIC contains a Federal Agency Smart Credential Number (FASC-N) on its integrated circuit chip.The FASC-N uniquely identifies each card.When a TWIC is read by a card reader, the FASC-N is one of the pieces of information the reader obtains from the card.Due to a card production system error, the number of characters in the FASC-N on some TWICs was shortened (truncated), causing readers to not recognize the card as a valid TWIC.

What is the issue with improperly encoded TWICs?.

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