The Most Dangerous Three Digits in an Intelligent Mail Barcode
August 29, 2023   Dave Lewis

My favorite scene in Young Frankenstein is when Igor sculks after hours in a brain depository in search of a brain for the creature.  He drops the brain he was supposed to get, so he chooses the one next to it, clearly labeled, “Abnormal Brain!  Do Not Use!”  Alas, they use it, and you know the rest of the story.  (If you don’t, stop reading this and watch it immediately. Mail isn’t everything)

The Service Type Identifier (STID) is really the brain of the Intelligent Mail barcode (IMb).  It is three digits that tell equipment reading the barcode what they should do with the mail.  It may indicate the class of mail, whether the mailer wants tracking or not, if its ballot mail or political mail, and so much more.  There are a lot of them – a whole table of them that you can access here:

You probably don’t think a lot about STIDs – in most cases your presort software just does them, based on what kind of mail you are preparing and what services you want.  But be careful – danger lurks in those three digits!

The other function of the STID is to tell the Postal Service how you want to handle UAA (Undeliverable As Addressed) mail.  Again, there are a few common selections that your presort software may well handle.  But, with recent changes to ACS (Address Correction Service), including the elimination of manual corrections on automated mail, some mailers are wading through the jungle of STIDs.  There are a lot of possible choices for ACS.  To name just a few:

  • Address Service Requested – Options 1 and 2;
  • Change Service Requested – Options 1 and 2;
  • Return Service Requested – Option 2 (I’m not sure what happened to Option 1.  Have you seen it?)

There are more options than these, and they are cross matched against class of mail, desire for mail tracking or lack thereof, type of mail, and more.  Many of them are free for Full-Service mailers, but some of them are the opposite of free, as in “really, really not free.”  If you dig through the STID table you will see lots of asterisks, foot notes, and dollar signs next to certain categories.  The dollar signs in the STID table are not like in restaurant reviews where one dollar sign means “pretty good deal.”  Any dollar sign on this table is not a good deal.  If you see a dollar sign, move on.  To most mailers dollar signs should be replaced with a stop sign.  Here are some of the foot notes from USPS:

Look at that last one – even the Postal Service doesn’t want you to waste your money. 

Why do these STIDs even exist?  Good question!  Some mailers are sending out very expensive items, and if they cannot be delivered, they want to get them back.  They’re willing to pay the return postage. 

Because of the recent changes in ACS, we have had a couple of clients send projects recently with the wrong STID – it had been provided by their presort software because they didn’t ask for what they wanted correctly.  Fortunately, our team caught it before the mail was created, and the correct STID replaced the wrong one.  The error would have cost them thousands of dollars.  It’s an easy mistake to make. 

If you are ever in doubt about what STID you should be using for a particular mailing, or the type of ACS that makes sense for you, reach out to us!!  SnailWorks has some of the premier experts on ACS services in the nation, and they love talking about this stuff.  You don’t need to be a customer to access this resource, and we’ll still tell you the right answer. 

Make sure you don’t use an abnormal brain in your next mailing – trust SnailWorks!