Before your next trip, take these 7 steps to protect your finances

Picture this: it's the last night of vacation, everyone's gathered around the dinner table, and when you try to pick up the tab, your card gets declined. Or maybe you're attempting to send money to a family member abroad, only for the transfer to stall without explanation. Frustrating as these moments can be, they're often a sign that your bank's fraud detection system is working exactly as intended.

According to Jennifer White, senior consultant in the Banking & Payments Intelligence practice at J.D. Power, the issue usually comes down to one thing: your spending behavior suddenly looks different. "When a customer is traveling, the way that they move money is different than their everyday spending experience," she tells CNBC Select. That change in pattern is often enough to trigger automated fraud alerts.

So what exactly raises those red flags? Here's what travelers should know, plus the steps to take before departure to avoid financial disruptions.

When you're at home, your spending is pretty predictable. You go to the same grocery store, fill up at the same gas station and maybe order from the same few restaurants. Your bank learns those patterns, and travel breaks all of them at once.

"When a consumer travels, they tend to increase either debit card or credit card usage in an area that is unfamiliar," White says. "It's not only unfamiliar in terms of their card issuer noticing that they're in a different location, it's also unfamiliar to the consumer. They're not at their normal grocery store. They aren't going to their regular corner pharmacy."

Just as important as where you're spending is how you're transacting. Travel tends to spike peer-to-peer transfers in a way that everyday life doesn't. From splitting a hotel room over Venmo, reimbursing someone for a group excursion on Zelle, to sending money internationally, all of it looks unusual to a system that's used to seeing you just pay your utility bill and grab coffee.

There's often a disconnect in how travelers prepare for a trip. White points out that many people will spend time focusing on finding a no-foreign-transaction-fee credit card, or even open a new bank account specifically for travel, yet they won't take the time to learn how to lock that same card if their wallet gets lost or stolen.

"They don't plan for the negative," White says. "If we put even as much effort into being prepared in that moment as we put into ensuring that I'm not going to pay a fee, that could be a game changer."

The good news is that being prepared doesn't take much. Here's where to start before your next trip.

Plan to use a VPN on public or hotel Wi-Fi

Logging into your financial accounts on an unsecured network is one of the easiest ways to expose your information. A VPN, or virtual private network, encrypts your connection so your data isn't visible to others on the same network. That matters most when you're connecting to Wi-Fi in public spots such as at airports, hotels or cafes, where anyone on the same network could potentially intercept unencrypted data.

If you want a reliable paid option, NordVPN is one of the most well-known names in the space for a reason. It works in 130+ countries, has strong security features and is straightforward enough to use even if you're not particularly tech savvy. You basically just open the app and turn it on.

Proton, on the other hand, offers a free VPN option that we recommend since it has many of the same security features as the paid version that it also offers. The free tier offers encrypted data cloud storage access and secure email services.

For those with a need for speed, Hotspot Shield turned out to be the only VPN that regularly improved speed compared to a non-VPN connection in our tests.

And if you're traveling with family or a group and want everyone covered under one subscription, Surfshark lets you connect unlimited devices on a single plan, which is rare among VPNs. It has servers in 100 countries, doesn't store your data or track your activity, and the Surfshark One bundle adds extras that are actually useful for travelers, like real-time alerts if your credit card or email shows up in a data breach and antivirus protection.​​​​​​​​​​​​​​​​

Lastly, if you're can't find a VPN that connects with your device, try ExpressVPN. The service offers assistance for Windows, Apple, Android, Linux, Chromebook, Amazon Fire, Apple TV, Roku, Chromecast and more.

Consider a travel eSIM

An eSIM is a digital SIM card built into your phone that lets you activate a local or regional data plan without swapping out a physical SIM. Instead of connecting to unknown Wi-Fi networks abroad, you get your own mobile data connection, which is generally far more secure. It also means you're not stuck hunting for Wi-Fi every time you need to check your bank account or transfer money.

Airalo offers one of the largest networks among eSIM providers that CNBC Select reviewed, with coverage in more than 200 countries. New users can qualify for a complimentary 1GB eSIM service if traveling to China, Greece, Japan, Portugal, Spain, Turkey, the U.K. or the U.S.

If you're traveling somewhere with a tight budget or just need coverage for a short trip, Saily offers plans starting at $1.99 across 200+ destinations, with plan lengths ranging from seven to 180 days. It was built by Nord Security, the same company behind NordVPN, and comes with built-in ad blockers and web protection tools against malware and phishing sites.

Set up real-time transaction alerts

Passively checking your statement when you return home from your trip isn't enough. Turn on notifications before taking off so you know the moment a transaction has been made in real time. This way, you can flag something suspicious right away rather than when it's too late. Most banking apps let you customize alerts by transaction type or amount, too, so you can set it up to notify you any time a purchase is made, no matter how small.

Enable multi-factor authentication

If someone ends up getting your login credentials, multi-factor authentication adds a layer that makes it significantly harder for them to access your account. It works by requiring a second form of verification, usually a code sent to your phone or email, before anyone can log in. Even if a bad actor has your password, they'd still need access to that second factor to get in.

Know how to lock your card

Find the card lock feature in your bank's app before you travel. If your wallet gets stolen, you want to be able to act in seconds. Most major banks have this built into their apps under account settings or a security center but the location varies, so it's worth finding it now rather than scrambling to figure it out in a panic abroad.

Use credit over debit

Credit cards typically offer stronger fraud protections and make it easier to dispute charges without your actual bank balance being affected.

Notify your bank about your trip

Letting your bank know of your travels ahead of time won't necessarily keep your account safer, but it can prevent a declined card from ruining a dinner, and it's a simple step that takes two minutes. Most banks let you set a travel notice directly in their app under account settings or by calling the number on the back of your card.​​​​​​​​​​​​​​​​

At CNBC Select, we work with experts who have specialized knowledge and authority based on relevant training and/or experience. For this story, we interviewed Jennifer White, senior consultant in the Banking & Payments Intelligence practice at J.D. Power.

At CNBC Select, our mission is to provide our readers with high-quality service journalism and comprehensive consumer advice so they can make informed decisions with their money. Every cybersecurity article is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of cybersecurity products. While CNBC Select earns a commission from affiliate partners on many offers and links, we create all our content without input from our commercial team or any outside third parties, and we pride ourselves on our journalistic standards and ethics.

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