Evacuees arrive to seek shelter with Red Cross volunteers at the George Brown convention center after flood waters of Hurricane Harvey forced them to leave their homes in Houston. (EUTERS/Marianna Parraga)

If you fly Southwest Airlines and have a few miles to spare you can help victims of Hurricane Harvey by donating miles to organizations supporting the recovery effort in Texas.

At this Southwest Airlines site you can donate miles to a variety of charities including two likely to be focused on recovery efforts in Texas: American Red Cross and All Hands Volunteers.

The Red Cross also is accepting donations of frequent flier miles. Here are details of how you can make a donation.

In addition, United Airlines is offering bonus miles to individuals who make cash donations to the American Red Cross, the Greater Houston Community Foundation, Airlink Operations USA and Americares. Find the link here.  United said they will match the first $200,000 raised. United Mileage Plus members who donate $50 to$99 will receive 250 award miles; $100 to $249 will receive 500 bonus miles and members who donate $250 or more will receive 1,000 bonus miles.

As of Tuesday, more than $1 million had been donated. Donations must be made by Sept. 15.

Members of American Airlines’ AAdvantage mileage program will earn 10 bonus miles for every dollar they donate to the American Red Cross from now through Sept. 15. There is a minimum $25 donation. So far, more 2,400 people have donated more than $500,000. More details are available here.