Spongebob's best friend is Patrick Star. Throughout the series, Spongebob and Patrick are shown to have a close bond and spend a lot of time together. They often engage in various adventures and mischief together, supporting and caring for each other. Patrick is always there for Spongebob, offering him advice, helping him out, and being a loyal and supportive friend. Their friendship is a central aspect of the show and is depicted as strong and genuine.