For many of us, summertime and vacation go hand in hand. But just because summer is a good time to get away for some people doesn't mean that it's the right time for you -- especially if your finances aren't where they should be. Here are a few reasons to consider postponing this year's vacation.

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1. You can't actually afford it

Planning to use a credit card to finance your upcoming trip? You're better off giving yourself time to save. Carrying a credit card balance can cost you even more money over time because of the interest charges you'll rack up. Let's say your vacation will cost $5,000 but because you don't have the money, you put it on your credit card and take two years to pay it off. At 12% interest (which is what many cards today might charge), you'll lose about $650 to interest fees -- money that can go a long way toward your next vacation. If you don't have the money to pay for your vacation, it's a sign that you shouldn't be taking it in the first place.

2. You're behind on retirement savings

Actually having some money on hand to pay for your vacation is certainly a good start. But if you're behind on retirement savings, you should invest that money for the future rather than blow it on a weeklong jaunt. Say you're looking at spending $5,000 on a vacation. If you sock it away in a retirement account instead, invest it at 8% annually (a reasonable goal for a stock-heavy portfolio), walk away, and check your balance 30 years later, you'll have amassed an impressive $50,000. Now if your retirement savings are on track and you have the money to spare, by all means, go ahead and treat yourself to a nice vacation. It's important to save for retirement, but you also deserve to enjoy your life as you go along. But if your retirement savings balance isn't where it should be, better to do the responsible thing and use that money to catch up.

3. You're saving for a major milestone

It's always nice to get away and unwind. But if taking that vacation means postponing a major life purchase or goal, you may want to think twice before you book those plane tickets. If, for example, you're hoping to buy a house or get married in the next year or two, the amount you spend on a vacation could spell the difference between meeting that goal or having to wait for six months, a year, or even longer.

4. You're already in debt

Let's say you come into unexpected money, like a bonus or tax refund, and decide to use it for a vacation. While you may not have to take on more debt to finance your trip, if you're already in debt, you're better of using that money to pay off your existing loans. Imagine you have $15,000 left on your student loans, and that you have another eight years of payments at 5% interest. If you use your vacation money to make a $5,000 dent, you'll reduce your monthly payment from $190 to $126 and save yourself over $6,000 in interest over the life of your loan.

5. You might save money by traveling off-peak

Traveling during the summer often means paying more for destinations across the U.S., Europe, and Canada. Wait to travel at a less popular time, such as mid-winter or early spring, and you might slash your vacation costs by hundreds of dollars. Let's say you're able to book a flight and hotel for $500 less during the off-season. If you take that $500, invest it, and score an 8% return, over the course of 30 years, you could grow it into $5,000 without having to wait too long to enjoy that trip.

While foregoing your summer vacation may not be ideal, you're better off postponing if doing so makes the most financial sense. Besides, if you start saving now, come this time next year, you'll be in a much better position to enjoy a vacation without having to worry about its impact on your finances.

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