Have you heard the saying about how being nice costs you nothing? While this is largely true, there are several instances where being nice can actually result in money losses. For example, people with an agreeable personality may not be management’s first pick for a supervisory position since they’re too focused on being liked, and may also hesitate to request a raise for fear of appearing greedy.

[See: 11 Ways to Save Time and Money.]

Aside from income, how else does agreeableness, or being “too” nice, cost consumers? As we approach the season when our behavior is judged as either “naughty” or “nice,” consider the following instances when being the latter can actually cost you.

1. When you’re overcharged. Overages and incorrect charges happen more often than you might think. One of the worst offenders is medical providers, whose Medicare billing error rate was estimated at 49 percent from a 2014 study conducted by NerdWallet. In that study, 63 percent of Americans reported receiving medical bills that were costlier than expected. Reviewing bills, receipts and other purchase confirmations is key to spending what you expect. But it doesn’t stop there. If there is an error, don’t let your niceness keep you from contesting the charge. In fact, politely pointing out the error is often more effective than being aggressive about the request. After all, the people behind the error are just that — people — who, like you, make mistakes now and again.

[See: 12 Ways to Be a More Mindful Spender.]

2. When discounts aren’t applied. It’s happened to all of us at some point: A grocery item rings up for more than its shelf price, a coupon you applied didn’t take, or an apparel item was incorrectly restocked to the sale rack. It may be easier to dismiss these moments and pay full price, but it’s actually a disservice to you and to the merchant. In many cases, retailers will honor the price listed for a product, even if it’s in the wrong location or labeled incorrectly. After all, it’s not the customer’s fault that the error occurred. Furthermore, finding out a coupon or discount wasn’t applied can discourage you from using them in the future, which is a disservice to your bank account. No process is perfect, but when you overcome your desire to be nice and just let things go, you’re actually helping systems work more efficiently.

3. When a sale item is no longer available. One of the keys to saving money on items you buy regularly is to stock up during sale time. Sometimes, other consumers have the same idea as you, and you arrive to the grocery store to find an empty shelf. It’s easy to shrug your shoulders and move on to the next item on your list. However, you are entitled to a rain check, or a voucher, which you can redeem for the sale price when the product is restocked. Before you decide that it’s too much trouble to have a store clerk or manager get you a rain check, consider the question cashiers ask when you check out: “Did you find everything you needed today?” This isn’t just a blanket statement: It’s a genuine question that requires an honest response, something any nice person is capable of giving.

[See: 11 Expenses Destroying Your Budget.]

4. When you fail to shop around for better rates. Being brand loyal has its benefits, but to save the most money, it literally pays to shop around. This is especially true in the case of auto insurance, which made headlines last year when its practice of price optimization ruffled the feathers of loyal customers. In an interview with NPR in 2015, Bob Hunter, director of insurance for the Consumer Federation of America, said some auto insurance companies will give loyal customers “a 10 percent discount after they’ve raised your rate 25 percent.”

Shopping around for insurance every year, including policies for your car, your home and your health, is key to managing household costs. But these savings don’t stop at insurance policies. Comparing prices on everything from vehicles to hotel rates to medical procedures often results in considerable savings. This process can be uncomfortable for personalities who prefer not to rock the boat by switching providers or asking about other options. However, in some cases, the savings can add up to thousands of dollars.

5. When you feel obligated to buy something. In an effort to be courteous, some consumers let sales pitches go too far and end up buying something they didn’t expect to. This is actually a common sales tactic called “assuming the sale,” whereby the salesperson uses language that makes it seem like the consumer has already agreed to buy something. This can create a false sense of obligation which polite consumers will use to justify their purchase. However, recognizing sales tactics for what they are can help everyone make smarter spending decisions.

6. When you accept all invitations. Saying “no” can be tough for a lot of people, leading to over-packed schedules and dwindling bank accounts. In addition to the potential exhaustion from accepting every social invitation thrown at you, the costs of these commitments add up. More often than not, politely declining an invitation is not a big deal for the person organizing the event. The more practice you have saying “no” to invitations that simply don’t fit your budget, schedule or interest, the more money you’ll have in your pocket for pursuits that actually bring you joy.

While Santa would prefer you to be nice this year, be sure to balance your agreeableness with the desire to remain financially solvent. Otherwise, there’s not much the man in the big red suit — or anyone — can do for you.

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6 Ways Being Too Nice Costs You Money originally appeared on usnews.com