Alaska Airlines and Horizon Air have launched electronic boarding passes for travelers flying from Anchorage, Boise, Denver, Fairbanks, Las Vegas, Portland, Seattle, San Jose and Spokane. The airlines plan to expand the option to other cities later in the year and as of last month, paperless boarding will be offered to customers traveling from the following cities in California: Burbank, Long Beach, Ontario, Palm Springs and Sacramento.

To use the new paperless boarding system, check in online with your cell phone or PDA at mobile.alaskaair.com from 24 hours in advance, up to one hour prior to departure. After checking-in, save or bookmark the electronic boarding pass Web page. Instead of presenting a piece of paper, you can show your cell phone or PDA to the security officer and boarding agent who will scan the encrypted barcode and verify your identity.

Alaska Airlines is the fifth airline to introduce electronic boarding passes, following Continental, American and Delta (Northwest). Paperless boarding has been introduced at 30 airports and the TSA publishes a full list of the airlines and airports that allow you to board the plane without a paper pass at http://insideflyerus.wpengine.com/link/?2259

While you won’t need to worry about losing your boarding pass at participating airports, be sure your cell phone is fully charged.