Frequent business travelers might have to factor in new cost when abroad this year: Sky-high fees for international mobile phone calls and data use.

While carriers such as Verizon, AT&T and Sprint have made it so the new generation of mobile calling applications -- including Skype Mobile, iCall and Talkatone -- work on business smartphones, they've also been raising per-minute call rates, the cost to send and receive texts, and fees for visiting a website or downloading a file. If you travel to Sweden, for example, Verizon will charge you $1.29 per minute or 99 cents if you prepay for a discounted plan. Take the train to Slovenia and you'll be charged $1.99 per minute, or $1.49 with the same discount.

Text rates are similarly steep. For example, AT&T charges 50 cents for each text sent when overseas. Data rates can run from $5 up to $20 per megabyte, or enough to download just a few Web pages.

The phone company representatives I spoke with all say the higher fees reflect the overall cost of mobile roaming internationally. That means the impact on your bottom line when using your mobile device internationally can be significant.

Follow these four tips to make sure you don't get a monster phone bill the next time you travel abroad:

1. Call your phone carrier before you travel.

All major carriers offer online international sales-support staff and discounts for calling in and planning ahead. So call them and make sure you fully understand these issues:

• The cost to call back to the U.S. from your overseas destination. In-country calling back to the U.S. is usually more expensive than calling from the U.S. to another country.

• The cost to call another country -- that's not the U.S. -- when abroad. These calls can be even more expensive to make.

• The difference between the cost of calling another mobile phone and calling a landline. Mobile phones are usually much pricier to call.

• The fees for sending and receiving text messages. Sometimes these cost 10 times the standard price when abroad.

• How your carrier bills video and audio content sent over text messages. Expect a major bump in rates, if the service is supported at all.

• How your carrier meters Web access. Data rates can vary dramatically by country.

2. Use Wi-Fi for calling, messaging, conferencing and accessing the Web to avoid international roaming charges.

Reference your phone's manual or contact a representative at your phone carrier and ask him or her to walk you through the process of optimizing your phone for overseas use. This usually involves the following steps:

• Find what is usually called the "settings" area. This is the place where your smartphone controls many of its functions, including how it connects to the larger cellular network. Keep in mind that most smartphones use both a cell network and a local Wi-Fi hotspot to communicate, so there may be several screens you'll need to look at.

• Turn off international roaming. This is the signal that is represented by a vertical bar logo in the upper right side of your phone’s screen. The more bars you see the more money you'll likely have to pay.

• Turn on your Wi-Fi connection. You should notice concentric half circles on your screen, usually next to your network access bars. The more circles you see, the less money you'll owe.

Remember, roaming begins as soon as you cross international borders. Also, many phones have features that limit updating email and social networks only over Wi-Fi networks.

3. Take calls only from clients.

As hard as it may be, stay off your cellphone as you wander the antiquities of, say, Rome or Athens. My rule of thumb is that my friends and family will understand if I don't call. My clients will not. So, I take client calls only and do everything else -- dialing out, calling my mom and checking my email -- using a low-cost Wi-Fi connection.

4. Consider using smartphone calling apps.

These can be big money-savers since they use low cost Wi-Fi connections instead of pricey international cell networks to provide service. Skype Mobile, for example, charges about 30 cents per minute for a call in Italy. I also like Palo Alto, Calif.-based Tango's app, because it offers a free video phone service. And if your business supports what's called session initiation protocol (SIP) mobile service -- that is the standard used by such tools as GoogleVoice -- consider Czech Republic-based Acrobits's Softphone app ($7 to download). The app is designed to work with more company-oriented internet calling technologies and should provide a more professional experience than other services.

Master these four steps and you may stand a good chance of coming back from your overseas trip with some new business and without a whopping cellphone bill.

This article was written by Jonathan Blum and published in Entrepreneur magazine.