My stupid credit card mistake

This guest post comes from J. Money at Budgets are Sexy.

I did something very stupid: I used my credit card instead of my debit card at the ATM last week. Three different times. The stupid cards look so much alike.

So, this means that:

• Each transaction was treated as a cash advance -- charging me $15-plus in total fees just for swiping them.
• I will be charged interest on this money from the day I got it until it's completely paid off. Which means that even if I do that today (which I'm going to do), and it registers tomorrow or the next day, I'm already looking at 10 total days' worth of interest.
  • Bing: Interest rates on cash advances

Not fun, especially since I already have a $1,800 balance on the card from the past month that I'm working to pay off.

• Video: 3 ways to raise your credit score fast

How to prevent this

When I tweeted/Facebooked about this, I got a couple of really good ideas on how to prevent this in the future. Maybe this will help you to not be an idiot too.

• Keep different PINs. If you have a different PIN for each card, you will catch yourself making this mistake when the ATM denies you. (And if you still don't get it, it doesn't matter since it won't give you the money anyway.) Thanks for the tip, Matt.
• Label each card with a Sharpie. If it's a "house" card, write "house" on the front of it. If it's for gas, write "gas," etc. It'll be another reminder to use the right card so you don't goof up. Big thanks to Jessica for that one. And Jen says nail polish works even better; it doesn't wipe off.

Moral of the story? Pay attention. And fix your wrongs ASAP before you cost yourself even more money down the road.

More from Budgets are Sexy and MSN Money:

• Your take: Lending money to friends and family
• Think you could live on a houseboat?
• What would you do with an extra $1,000?
• Secret cash advances worry wife
• 12 ways I don't set an example
• Bribed -- to pay off credit cards