ANCHORAGE, Alaska — Alaska Airlines says in a letter to its customers that it is increasing the cost of companion fares available through its Visa Signature card from $50 to $99. The price increase go into effect Oct. 1. The airline says it’s the first increase in companion fares in 10 years and still a great deal.

The airline is making another change to the credit card’s terms. It will eliminate the 2,000 free anniversary miles it has granted annually to cardholders, starting on Dec. 31.

Company spokeswoman Bobbie Egan says the airline is trying to offset the rising cost of the credit card program, while avoiding increasing the annual fee.

The letter explaining the changes was sent to customers in late July.