Back in September, I reported that U.S. credit card debt reached an all-time high, with the average household owing a whopping $16,000. And while it's not just our credit cards we're abusing -- we're also borrowing way too much for things like automobiles and college -- credit card debt is pretty much the worst kind to have. Not only can carrying too high a balance ruin your credit, but it can also be one of the costliest mistakes you'll ever make.

That's why it's crucial to work on shedding whatever credit card debt you've accrued, and the sooner you do, the better. The good news? If you play your cards right, you can slash your debt substantially by year-end, despite the fact that it's only about a month away. Here's how.

A woman holds her head in her hands, looking stressed as she pores over a pile of papers on a table.

IMAGE SOURCE: GETTY IMAGES.

1. Get a side hustle

Paying off credit card debt requires one thing above all else: extra cash. So if your paycheck doesn't give you much wiggle room, it's time to consider a side hustle. Now, in fact, is the perfect time to pick up additional work, because retailers, restaurants, and hotels frequently need extra hands on deck during the holiday season. If you're willing to forgo a bunch of downtime in the next month, you might come away with a nice chunk of cash to pay down your balance. Of the estimated 44 million Americans who currently work a second gig, 36% bring home over $500 extra a month as a result. And that could instantly help you cut your debt.

2. Cash in your holiday gifts

We all get things we don't really want for the holidays, whether it's a gadget you have little use for or a gift card to a retailer that's no longer convenient. But rather than let those reject gifts take up space in your closet or desk drawer, exchange them for cash and use the proceeds to pay down some debt. You can unload unwanted goods online, or post them to your social network and see if you have any takers. You can also use sites like CardCash to trade gift cards for actual money. Just be aware that if you go this route, you'll generally lose a percentage of each gift card's value. Still, it's better to get rid of a $50 gift card you'll never use and have $40 in cash.

3. Ask for cash in lieu of gifts

While you may not have the nerve to ask your friends and colleagues for cash instead of store-bought gifts this season, when it comes to family, there's no need to be shy. Talk to your parents, grandparents, siblings, and whoever else tends to shower you with gifts, and come clean about needing the money. With any luck, they'll skip the scarves and sweaters and give you what you really want. And once they do, you can use that money to chip away at your outstanding credit card balance.

4. Use your bonus wisely

If you're getting a bonus at work this year, you may be tempted to blow that money on a vacation or new electronic device. Don't. No matter how much extra cash you're looking at, you're better off applying it to your credit card debt and watching that balance go down. If you really can't bear to part with your entire bonus, set aside a small portion of it for fun purposes, and use the bulk of it responsibly. That way, you'll get a small reward for earning that cash.

The sooner you lower your outstanding debt, the less money you stand to throw away on interest. So if you want a stronger financial start to 2018, use the next four weeks or so as an opportunity to pay off at least some of what you owe. You'll be happier for it in the long run.

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