My personal budgeting system involves using a different bank card for each area of spending (one card for food, one for travel etc), and with a stack of cards comes an obvious challenge: how to remember all your pin numbers?
Here’s the simple system that I’ve been using for years, it’s practically fool proof and I recommend it to anybody who has multiple bank accounts or suffer from a poor memory. Everyone who has tried it tell me they love it and that they use it every day.
Grab a bank card and we’ll make a pin number that you’ll never forget. The new pin number will be split into two parts:
Part 1: Your ‘Lucky’ number: Choose a secret number to make up the first 2 digits of your pin number, this can be your lucky number, year of birth, anything that is special to you.
Part 2: Your ‘Public’ number: Choose 2 digits from the long card number to be the last 2 digits of your pin. Perhaps the last 2 digits? Or the final digit repeated twice? Whatever you feel is easy to remember.
Now you have a new pin number that is constructed from a well known ‘lucky’ number and another number that is hidden in plain sight as only you know how to find it.
The beauty of this system is that you don’t need to memorise your pin because you can easily figure it out when you need it, all it takes is a quick glance at the long number for the last 2 digits. It’s very satisfying to pick up a card you haven’t used in 3 years and instantly know the pin number, because this system works just as well with rarely used pins as with those that you use every day.
It’s an amusing irony that in order to stop forgetting your pin number you must first stop trying to remember it.
The simple example I’ve given above can be changed in a number of ways to improve security. For example: if you have cards from multiple banks then you might like to use a different ‘lucky’ number for each bank. Perhaps ‘Barclays’ could have a lucky number of 01 because it’s the first bank account you opened? Or maybe it should be 02 because it begins with ‘B’ and which is the second letter of the alphabet?
The ‘public’ number could be a calculation instead of being read from the card? For example you could multiply the last 2 digits of the long number together? Or you could take the final 2 digits and add the value of the first digit?
You can complicate the system to increase security if you want to but in my experience it’s best to keep it simple because doing sums in your head is no fun when you’re tired or drunk. And anyway, the chance of someone stealing one of your pins then reverse engineering even the basic system described above is practically zero.