You might go for years without needing a credit score or having any reason to even know what's in your credit history. Some people may never need a credit score.

In fact, some people are proud of not having scores or not worrying about them. They say credit scores are for losers, or at least for debtors, because they say you can't have one without being in debt.

Thirty years ago, that may have been the case. Nowadays, not having a good credit score can be a costly mistake. Here are three reasons to work on your credit score now.

1. You don't know when you need a credit score
Unless you're living off the grid somewhere, there's a good chance you'll need a credit score sometime -- possibly sooner than you think.

Credit scores are becoming a bigger part of our lives as they become easier to access, as more people use your score -- not a personal judgment or a gut feeling -- to decide whether to do business with you.

You'll need a credit score to buy a car, and possibly to rent an apartment or business office.

If you apply for certain types of jobs, be ready to show your credit score. In the past, employers wanted to be sure you weren't in financial hot water before they let you manage client cash or be in other positions of financial responsibility. Increasingly, employers may ask to see a credit report for any job.

Starting your own business? Your credit score can help decide whether you get a business loan.

For most people, the biggest reason they need a credit score is so they can buy a house. I've known people who didn't believe in mortgages, so they lived in trailers in the Mojave Desert. For most of us, that would be a long commute, and we wouldn't like the kitchen. Mortgages are a fact of life, and if we can't change the game, we'd better learn the rules.

Some people will always get a loan with a skimpy credit history or a less-than-optimal score. They'll almost certainly pay a higher interest rate, however. Over the long run, an insufficient or lousy credit history will cost you a lot of money.

2. It takes time to build a good score
When you decide you'd like to buy or refinance a house, it's a bit late to start working on your credit score.

You may be able to build a decent score from scratch in a year or two, but an excellent score can take longer. That's because a major portion of your score comes from the length of time you've had open accounts. Potential creditors aren't that impressed with a perfect payment history of a couple of months or so.

3. Building a score doesn't have to hurt your financial position
There's no truth to the idea that you can't build a credit score without carrying a balance on your credit cards. You don't need to use a card a lot, and you certainly don't need to buy anything you don't need. Put a tankful of gas on your card occasionally, pay the balance off before it's due, and you're on your way to an excellent score.

You can also bolster your credit history by asking other creditors, such as the phone company or your landlord, to report to the credit bureaus. This adds to your credit history without putting you in debt.

To build an outstanding score, you should have more than credit cards in your credit history. If you're buying a car anyway, you might pay it off quickly with a short-term loan. Don't buy a car, or a better car, just for your credit score's sake, however. If a move isn't good for your total financial picture, in the long run it won't be good for you -- or your credit score.

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