Check this out

There has been a revolution in supermarket checkouts over the past 12 months or so. Supermarkets are demonstrating a hitherto unprecedented level of trust in their customers by allowing them to check out their own shopping. This saves on wages and potentially saves the customer time. There is a risk that some customers will take advantage of this idea by not checking items out, or by committing card fraud - however, these risks can be mitigated against to some degree with random checking, and any rise in theft must have been shown to be less than the benefits to the supermarkets.

There are a few systems in place right now:

Scan at checkout

Seen in Tesco, B&Q

The idea here is that the customer shops as usual, and then proceeds to an automated checkout where they scan each item. Once scanned, the item is placed into a 'bagging area' where a scale checks the weight of the item matches what was scanned. As bags become full they can be removed.


No special training is needed. A voice gives instruction. The customer can decide to use the system after shopping.


Some items don't scan well - and there isn't an obvious way to type in the number from scratch. Some light items do not register as being placed in the bagging area. Once the system has been used a few times, it is easy to 'run ahead' of the system and scan faster than it can cope with. The insistence that every item is placed in the bagging area adds delay. There is no obvious way to tell the system 'here is one pot of yoghurt, I have 5 more just like it'.


I will use these systems, but for more than a few items I find they're more trouble than they're worth. I find the voice nagging and slow. It'd be better if I could scan my clubcard at the start and it'd remember my preferences 'expert user, no voice' - these could be adjusted online.

Handheld Scanner

Seen in Sainsbury

The idea here is that as the customer shops as usual, they scan the barcodes of the items. At checkout, there is a 'fast' lane, where the customer's scanner is checked. Occasionally a random 'rescan' is done (I am guessing that the probability of a rescan goes up if previous scans were in error - and that some level of error will cause them to revoke the fast-track rights). The 'Electric Death' site suggests two errors lead to always rescanning. This seems too absolute to me, as wait long enough and virtually everyone would have two errors. There would have to be some 'aging' to this, i.e. an old error is 'worth less' than a new - and correct rescans improve the customer's rating (with new rescans counting for more than old). I'd like to know how this has evolved since the system was introduced.


A very fast checkout most of the time, and a running tally of the shopping bill.


Not every item is 'in the system', so occasionally there are 'problem items'. I assume this is because the scanner doesn't connect to the main database each time. These items must be kept separately and rescanned at checkout. Most of the time, if I get a problem item it'll remain on the shelf.

Why not record the barcode of the 'problem item' on the scanner and pass this to the checkout for checking on the main database?

The scanner does not adjust for offers in the running total. These are corrected for at checkout. Also, at checkout, the system has sometimes allowed a tagged item to go home without the tag being removed - this is a pain.

Some customer training is needed to use the scanner.


I like this system a lot - it operates as fast as the user and drastically reduces time at the end of the shop when you just want to 'get out of there'. The rescan is a pain when it happens, but seems intelligent (i.e. to reduce in frequency with accurate rescans). They will sometimes not have a 'fast track' lane open, but what's really nice is that if you approach the checkout with a scanner, and there are queues then they'll rush to open a 'scanner only' lane for you.

The big problem is that so far I've only seen it in Sainsburys. Also, the system is not connected between stores - if I register for the system at Store A, and go into Store B then I need to register there as well. This is rather daft in this day and age - the stores should be able to communicate this information.

Universal Problem

One big problem with all checkouts in the UK is the Chip and Pin device. This is usually mounted in an easy to see location, so the customer can't miss it. Unfortunately they were not designed in such a way that when the pin is entered, the keypad is obscured. Thus one can stand and read pin numbers as people type them - a recipe for muggers.(*) Why weren't they designed with a deeper 'shield' -so that if you needed to look you had to remove the hand - but with the hand in, the keypad couldn't be seen?

Ah well, as things stand right now - I'll shield my pin, and the mugger skimming numbers will focus on the easier targets all around me. An ex-colleague had his pin cloned by an oik who had the cctv trained on the card reader, they got the card number by freeze-framing the card as it went in, and the pin by watching the fingers - if the handheld is detachable, detach it to avoid this issue!

(*) I once decided to be helpful to a friendly-looking lady in a queue by saying that she should hide her pin for this reason, that she entered it in a way that the number could be read (I knew it by standing behind her). I got back 'if I get mugged in a minute I'll know who to blame then!'... yeah, muggers forewarn their victims! And they wonder why people aren't helpful any more?