Traveling overseas this holiday season?

You may have already packed a toothbrush, extra socks and an atlas. But there’s one additional item that can save travelers some serious money. That’s an international SIM card for the cellphone.

Travelers will see they are able to cut roaming charges as much as 65 percent if they use the appropriate SIM card, such as Brightroam.com’s international SIM card, according to the company’s data. And travelers can cut charges as much as 97 percent by using an in-country SIM card, with an example being Brightroam’s Mexico SIM Card, the company adds.

“We have all heard roaming charge horror stories, or even worse arrived home to a mobile bill hundreds of dollars higher than expected,” Doug Johnson (News - Alert), Brightroam.com’s director of marketing, said in a recent statement carried on TMCnet. “Once a SIM card is tucked into your phone, it’s out of sight and out of mind.”

As an added benefit to consumers, users only pay for calls they make. In addition, incoming text messages are also free of charge in several locations. Data charges are competitive so travelers can upload their vacation pictures.

Currently, the company is offering until Dec. 31, 2011, a deal where all Brightroam.com SIM cards are free of charge. These include the Australia SIM Card, China SIM Card, France SIM Card, German SIM card, Greece SIM Card, Netherlands SIM card, UK SIM Card, USA SIM Card and Switzerland SIM Card.

Brightroam.com also provides local mobile numbers for individual countries, North American call forwarding, and English-language support round the clock. Brightroam.com has coverage in over 200 nations, according to the company’s website. It also allows callers to keep their own cellphone numbers.

Brightroam is also offering this holiday season a gift certificate. Brightroam’s gift card lets traveling friends, relatives or colleagues “obtain everything they need to make affordable local calls when they arrive and also communicate affordably  with North America.” It comes in three denominations – $50, $100 or $200.