You’re not wrong to worry about getting scammed; fraud in general is on the rise (and anyone can be a victim), with losses attributed to various kinds of fraud topping $10 billion in 2023 alone. And good old-fashioned bank fraud is on the rise, too—including check fraud, which might seem surprising since paper check use has been declining since forever. Although we write fewer checks, the value of those checks has risen from an average of $673 in 1990 to $2,562 today, making them an attractive target.

But avoiding paper checks doesn’t insulate you from fraud. Paying for things online using credit cards or similar tools includes some built-in fraud protections, but there are times when using an e-check and having funds pulled directly from your bank account is preferable (when there’s a “convenience fee” for using a credit card, for example), or you might have money coming in via wire transfer. In either case, you’re suddenly faced with giving away your bank details—the routing number, account number, and wire transfer or SWIFT codes—in order to complete the transaction. And you might reasonably wonder if it’s safe to just give this information away.

The answer is: Yes, generally speaking. But that doesn’t mean you shouldn’t be careful.

Banking information to keep an eye on

A quick rundown of the relevant details we’re talking about here; when I say “bank details,” I mean:

Routing number: A nine-digit code that identifies your specific bank.

Account number: The number of digits in your account number varies. It’s a unique identifier for a specific account at the bank or financial institution.

SWIFT code: If you need to send or receive money internationally, you might need a Society for Worldwide Interbank Financial Telecommunication (SWIFT) code. This is a number between eight and eleven digits that identifies your bank.

ABA number: Also called a “wire routing number,” this nine-digit code is an alternative way to transfer funds internationally.

Most of these numbers are pretty easy to find. If you have paper checks issued by your bank, the routing number is printed on the bottom left, and your account number is printed to the right of that. And you can usually find your bank’s routing number and SWIFT and ABA codes by logging on to their website, calling and asking, or just looking them up online.

As I said earlier, your routing and account numbers are literally printed on your checks. These numbers are used in what are known as Automated Clearing House (ACH) transactions to move money between different banks and accounts. This means anyone who sees your check also sees your ACH info—and with that info they can commit some pretty easy fraud against your accounts. So when should you worry?

When it’s OK to share your banking details

First, take note of the fact that you share your routing number and account numbers all the time. Every time you send a check, sign up for direct deposit, or enter your banking info to pay taxes or a utility bill (or sell tickets on StubHub) you’re sharing those numbers. They’re out there. A few things to keep in mind:

Just having your account number is meaningless. No one can do anything with just your account number. They also need your bank’s routing number.

As noted, your bank’s routing number and ABA and SWIFT codes are public info and can be looked up online, so there’s no reason to guard those with your life.

So, when should you feel safe sharing your bank routing and account numbers? A few guidelines:

If you would be comfortable writing a check, it’s generally OK to share your bank details.

If you know why you’re being asked for this information—you’re setting up an account, or direct deposit, or paying a bill using ACH to avoid a fee, for example—it’s generally OK.

If there’s a legitimate, compelling reason the organization needs this info (e.g., direct deposit) or you have a compelling reason to offer it up (e.g., avoiding a fee if you pay via credit card or PayPal).

Keep in mind that when you give someone authorization to use ACH to access your bank accounts, you can always revoke that authorization, and you generally have 60 days to report fraud involving your bank account as an individual.

When you should worry

Of course, scammers can wreak serious havoc on your financial life if they get both your routing and account numbers, so you definitely do need to think twice before supplying them. Here’s when to worry:

Insecure communications. Never give your bank details to anyone who requests them via email or text.

Supplied links. If you’re sent a link to enter your bank details, be suspicious. Always go directly to the website of any business or organization to enter routing and account info.

Pressure. If you prefer to use another form of payment—a credit card, for example—but you’re pressured to give out your bank details, be suspicious.

Bottom line: the key is your account number. Scammers can’t do anything without that, and they can find out everything else on their own, so if you don’t give out your account number there isn’t much they can do to you. On the other hand, if you need to get paid via wire transfer or need to pay a bill using your bank account, it’s generally safe to provide your bank details as long as you expected the request. Just be wary if it’s unexpected, or if you don’t understand why it’s necessary to provide that information.