I have had my Barclays credit card a while now and previously never had any issues. I have spent money and withdrawn cash in Prague and Moscow, paying no fees or interest as I paid the balance in full.
However, last month I spent £1,538.40 in Valencia and instead of paying the full balance, I paid off £1,238.40. The bill was due on 4th June and I paid the amount by 22nd May. This left a balance of £300, my thinking being I would take the interest hit on the remaining £300 at approx 20% APR or similar, around £5 or whatever their minimum charge is (e.g. 20% of £300 is £60, divided by 12). I was surprised to see my interest on this £300 come out at £27.18, if my sums are correct then isn’t this about 108.7% APR? Maybe I am doing my sums wrong and this is actually how it works. I am hoping one of you more knowledgeable fine people can explain to me where I went wrong. Going forward I will pay in full, however I was expecting some Tax Free money to come back to my card, so left the balance as I wanted to make sure the card didn’t go in to credit, I won’t make that mistake again!