That puts United's policy more in line with that of its competitors Delta Air Lines and American Airlines. The airline is working with American Humane, an animal welfare group to improve its pet transportation program.
United reported to the Department of Transportation the highest number of animal deaths of any U.S. carrier: 18. American and Delta each reported that two animals died on their planes last year. Those figures refer to animals that were transported in the cargo hold, not the cabin.
United is also limiting when and where pets can fly because of concerns about high temperatures. United will not accept cats and dogs in the cargo hold between May 1 to Sept. 30 to or from Las Vegas, Palm Springs, California, Phoenix or Tuscon, Arizona.
United had suspended its pet transportation program following the death of the puppy and the two mix-ups in March. It has since started issuing brightly-colored bag tags for animals traveling in the cabin with passengers. The new rules announced Tuesday do not affect in-cabin animal transport, but CNBC reported earlier that it is reviewing its in-cabin pet policy.