Remember the old phrase “the check is in the mail?” That’s a bad idea today, according to the U.S. Post Office.

Scammers are targeting mail more than ever leading to loss of money and exposure of sensitive personal information. According to a report from Business Insider, banks issued roughly 680,000 reports of check fraud last year, up from 350,000 in 2021. The U.S. Postal Service reported about 300,000 complaints of mail theft in 2021, double the previous year’s total.

Mail became a particularly tempting target during the COVID pandemic when millions received government relief checks.

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“Despite the declining use of checks in the United States, criminals have been increasingly targeting the US Mail since the COVID-19 pandemic to commit check fraud,” the US Financial Crimes Enforcement Network wrote in an alert.

The most common type of check fraud related to the mail is “check washing,” where a criminal steals the envelope from your mail box and changes the payee’s name and amount of money that’s listed. USPS said its postal inspectors recover more than $1 billion in counterfeit checks and money orders every year, some of which have been altered through “washing.”

To help prevent mail theft, the U.S. Post Office recently deployed 12,000 security mailboxes across the U.S. The blue collected boxes will be placed in “high security risk areas” and will be harder for criminals to access.

USPS is also replacing its antiquated “arrow” locks with 49,000 electronic locks, a move that comes after the service reported that letter carriers have been targeted for their specialty keys that allow for box access. The new locks have already been installed in select cities with installation in additional major metro areas soon.

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How to prevent mail theft and fraud:

USPS has tips for protecting yourself against mail theft:

• Don’t let incoming or outgoing mail sit in your mailbox. You can significantly reduce the chance of being victimized by simply removing your mail from your mailbox every day.
• Safest way to deposit outgoing mail is inside your local post office or by handing it to a letter carrier directly.
• Sign up for Informed Delivery and get daily digest emails that preview your mail and packages scheduled to arrive soon.
• Keep an eye out for your letter carrier. If you see something that looks suspicious, or you see someone following your carrier, call 911.
• Customers are encouraged to report stolen mail as soon as possible by submitting an online complaint to the Postal Inspection Service at www.uspis.gov/report or calling 877-876-2455