We’ve been working aggressively to pay off our cards over the last year or so. Running the numbers on our situation has led to some surprising insights about the potential of a debt-free existence.

Let’s say you’re carrying the American average of $10,000 debt on your credit cards, but, rather than pay the insane 29% interest on most consumer cards, you were smart about it and moved the money to a 0% card. And let’s say you’re paying that money off at $400/month. That leaves you 25 months to pay the sucker off. Should you try to pay it off sooner?

Well, let’s take a look a what life would be like without the $400/mo payment. 400 times 12 months equals $4,800/year — not an insubstantial chunk of money. And, you’re paying taxes on that money for the privledge of sending it to the credit card companies every month. Assuming that’s around 30%, you have to earn $6,854 per year just to give it away to Uncle Sam and the bank.

Let’s say you make $65K per year: paying off the card completely would be like giving yourself a 10.5% raise! But let’s take that a step further: what if you paid off the card and invested half the monthly payment into a retirement account like a 401(k). You get to pocket $200 every month ($2,400 a year), but because a 401(k) is a pre-tax investment, you’re investing $285/mo in your future.

Knowing that many companies match retirement contributions — some match a dollar for every dollar you contribute — that means you could be saving as much as $570 a month, or $6,840 a year!

Now you’ve given yourself a 14% raise ($2,400 pocket money + $6,840 in savings), all by just paying off your credit cards as quickly as possible. And, note, that’s assuming that you’re not paying any interest on that debt — that adds a whole new level of urgency to paying off your cards ASAP.

A “friend of mine”:http://sapridyne.com calls the difference between his expendable income and his credit card debt his “shovel to hole ratio” — in other words, his ability to dig himself out of debt. Paying off your cards and saving the money for the future takes this analogy to a new level. Once you’ve got the hole filled, now you can start stacking bricks on it and really build something.

It’s a wonder more people aren’t doing this.