According to recent surveys, the percentage of pet owners who intend to dress up their pets in costumes for Halloween varies depending on the year and the survey. Here are the results from the available sources:

• In 2022, more than 75% of pet parents are planning to dress their pets up for Halloween and other fall occasions, according to a survey by PetSmart.
• In 2021, just over one fifth of survey respondents stated that they planned to dress their pet in a costume for Halloween in the United States.
• In 2020, a Rover survey found that 66% of dog owners were going to dress up their dogs for Halloween.
• In 2018, nearly 20% of the 175 million Americans celebrating Halloween planned to dress up their pets, according to a survey by Prosper Insights & Analytics.
• In 2022, 76% of pet owners said they "like" to put their pets in costumes for Halloween, and 30% of people are planning to dress them up more than once this fall season, according to a survey by PetSmart.

Based on these sources, it seems that the percentage of pet owners who intend to dress up their pets in costumes for Halloween varies from year to year and survey to survey, but it is generally a significant portion of pet owners.