Horizon Air and its sister carrier, Alaska Airlines, announced changes Thursday in fees and polices for checked baggage, ticketing and unaccompanied minor travel.

The changes become effective for tickets purchased beginning May 1 and travel beginning June 16.

However, many of the changes will not apply to the airlines’ mileage plan members, first-class passengers, those traveling to or within certain destinations and active-duty military.

Alaska and Horizon — the latter of which offers direct flights from Redmond Airport to Eugene, Los Angeles, Portland and Seattle — have revamped charges for checked baggage.

The airlines will charge $20 for each of a passenger’s first three checked bags. For bags four through 10, the fee will be reduced from $100 per bag to $50.

Compared to current fees, the changes will mean a $5 increase for the first checked bag, a $5 decrease for the second and a $30 reduction for the third.

Alaska and Horizon also will be cutting their waiting-time guarantee for luggage to arrive at the baggage claim, from 25 minutes to 20 minutes. If bags do not reach the baggage claim within 20 minutes from the time the flight parks at the gate, customers will receive either 2,000 air miles or $20 off a future flight.

For unaccompanied minors, the airlines will be charging $25 per child for direct flights and $50 each for connecting flights within the Alaska-Horizon system. Currently, the airlines charge a $75 fee for unaccompanied-minor travel.

Changing a flight within six hours of departure will soon cost $25, if space is available on the requested flight. Currently, a passenger can pay $25 or stand by for free. Customers making a change outside the six-hour window will pay the difference in fare price plus any applicable fee.

Beginning May 12, the airlines also will no longer hold a reservation for 24 hours without payment. However, for passengers who change their minds or need to change their plans, Alaska and Horizon will allow them to make one change without charge, or obtain a full refund, within 24 hours of their purchase. The holds will still be available for reservations through the airlines’ corporate online booking site, Alaska Airlines Vacations and for groups.

For more information on the changes, visit www.alaskaair .com.