If you make a call while you’re out of country, you might get nailed with major charges. But there is an option known as “callback companies” that can be worth it in some situations.

Here’s how it works: you sign up for callback service with companies such as ITL Kallback, Telestial or United World Telecom.

You tell them what number you’ll be dialing from—say your hotel room or cell phone—and they’ll issue you a unique phone number.

Dial that number, let it ring once, and hang up.

Then they’ll call you back with a dial tone so you can make your call.

It’s free to sign up, and charges are on per-minute basis, say 18 cents a minute to call the US from England.

So when would this service be useful? Well, if your cell phone doesn’t have a SIM card, you’ll get hit with major roaming charges on international calls.

This service also works well for checking voicemail.

And best of all, it gets around those astronomical charges for making calls in a hotel room.

Why? Because when you get that call back with the dial tone, the hotel registers it as an incoming call—which is entirely free.

Find out Everything You Need to Know About International Calls.

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