How is my credit score calculated?

Last Modified 16th of February 2021

Your credit score is a measure of how credit worthy you are and how big of a risk you pose to any creditors who lend you money. Not surprisingly then, your score is based on what previous information is available.

Every time you do anything that involves borrowing money, that information is passed on to credit agencies. But there is not one single score, each credit agency has its own way of calculating your credit score based on their own formulae.


The main three credit agencies are Experian, Equifax and Callcredit and you will have a different score depending on which one you ask. Either way though, the score is just an indicator of how good or bad your credit history is and the overall information will be much the same from either of those agencies.

So how is it worked out?

Well nobody knows the algorithm per sae, and they are probably very complicated anyway. But the things that affect your credit score are simple to understand…

To improve your credit score you need to add positive information. Positive information is anything where you have used credit ‘correctly’. This includes building up a credit card debt and then paying it off, it could also be paying a loan instalment or even paying your phone bill on time (unless you are on pay as you go, your phone bill is a form of credit).

You also need to avoid bad information, so try not to make payments late, don’t go past your overdraft limit or credit limit and don’t leave outstanding balances unpaid for long periods of time. Unfortunately it takes a relatively high amount of good info to cancel out a few blemishes, so being careful is important.

Coming to the score

Your actual score with any given agency will take into account all of this information; as I said, it is complicated, but using common sense you should already have a good idea of how your credit score might look.

As information gets older it is weighted less heavily, and occasional blemishes don’t hurt you anywhere nearly as badly as persistent mistakes. So a slip up here and there might not be as damaging as you thought, but more than a few and you have your work cut out!