There is no definitive answer to this question as it depends on a number of factors, such as the type and size of your UTV, the terrain you'll be driving on, and your personal preferences. That said, most UTV tires can be safely run at 20-30 PSI without compromising performance or ride quality. If you're planning on tackling particularly rough terrain, you may want to increase the pressure slightly to help prevent flats. Conversely, if you're mostly driving on smooth surfaces, you can decrease the pressure to improve comfort and traction. Ultimately, it's up to you to experiment and find the perfect PSI for your needs.