Are you getting ready to go on a cruise? Before you pack your cell phone, here’s what you need to know before you get nailed by hefty fees.

Many cruise lines offer connections to land-based mobile networks using a service called Cellular At Sea.

But there’s a big catch: you’re still paying international roaming rates.

And it may not be clear at the time, but if you use your phone out of sight from land, you are automatically using the system and will be billed via your regular phone service.

That can cost as much as $3 a minute!

Depending on where you’re cruising, it’s a good idea to wait until the ship docks and you can connect to land-based cell towers.

But depending on your plan, that can still translate into roaming charges.

To cut costs, alert your carrier that you’ll be traveling, and see if there is an international plan you can switch to, at least temporarily.

Also, don’t forget to turn your phone off when you’re not using it–you’re usually charged for calls that ring through, but not those that go directly to voicemail when your phone is off.

And try to remember one thing, you’re on vacation!

How about really disconnecting and leaving the phone behind … or at least at the bottom of your suitcase. Out of sight, out of mind.

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