Most experts recommend keeping only a modest stash of emergency cash on your person when you travel. But if you're flying to a destination like Cuba where American ATMs and credit cards simply won't work, you might not have any choice but to carry large amounts of cash. This means you’ll have to have this large amount of money with you in your carry-on bag during air travel on your international flights. Here’s what you should know about traveling with a large sum of cash or valuables at security checkpoints to your destination country and what the law enforcement powers entail.

Limits on Carrying Cash

Although there's technically no legal cash limit on how much money you can carry on a plane, if you're traveling internationally you must be prepared to declare amounts of more than $10,000 (10,000 USD) on your customs form, fill out a declaration form or FinCEN form 105, and be prepared for possible interviews with law enforcement to explain the amount of money you're carrying. Law enforcement agencies are trying to prevent money laundering, drug trafficking, and other criminal activity and illegal activity – that’s why there are so many hoops to jump through during airport security and customs declarations. Having a money order or traveler’s checks as your monetary instrument instead of US dollars or foreign currency can make it easier, if they’re something the country you’re going to will accept.

Where to Put Your Cash

That might sound like the start of a bad joke, but if you're traveling with a lot of cash, it's a serious consideration. Needless to say, don't put cash in your checked bags. Too many people have access to them while they're out of your sight, so if the money turns up missing it would be almost impossible to make a case for who took it. If you try to carry a wad of cash on your person, you're guaranteeing yourself a pat-down or at least additional screening by officers with the Transportation Security Administration.

Usually, the best compromise is to put the cash in your carry-on, secure it with a TSA-approved lock, and never let it out of your direct line of sight. If you're chosen for secondary (additional) screening, let the TSA agents know your bag contains cash and you need to keep it in your sight during the screening. Aside from any screening, keep your cash secure and out of sight. If you want to carry the cash in a money belt, you can put it on in the airport restroom after you pass through security.

Cash and the TSA

Again, there's no legal limit on how much cash you can carry through a TSA checkpoint. But the TSA or U.S. Customs and Border Protection may ask you to justify any unusual amounts of cash you're carrying, and your answers (or lack thereof) and general demeanor could trigger a report to law enforcement entities like the Drug Enforcement Agency that can, in turn, seize your cash. So the biggest takeaway is that if you're going to carry a large amount of currency, make sure you have a legitimate, legal reason for doing so – and leave yourself some extra time at the airport in case you must explain why you're carrying it.