Longest-running animated sitcom (by episode count)

According to Official Guinness Records,

The current longest-running animated sitcom on TV is The Simpsons (FOX, USA), which had aired 596 episodes by the close of its 27th season on 22 May 2016. The 28th season had already been commissioned.The Simpsons also set a number of other records, including most guest stars featured in a TV show and most Emmy Awards won for an animated series.

For a complete list of 2016 records, please visit 2016 Guinness Records in United States.

Other United States records that might interest you:

• Most eyebrows threaded in one hour by an individual
• Longest line of surfboards
• Largest square dance
• Fastest time to eat a hot dog with no hands
• Most jiaozi/gyoza dumplings eaten in one minute
• Oldest regular blood donor
• Most balloons burst by a laser in one minute
• Most beer bottles opened by chainsaw in one minute