What is the largest fish you’ve ever caught? Or seen? The largemouth bass is said to be mostly 5.5 kg and 18 inches in length but can go up to 22 inches. To date, the largest largemouth bass ever caught was 10.09 kgs and was caught by a farmer, George Perry, in 1932. Largemouth bass fishing may be popular, but world record catches are surprisingly less common as Mr Perry’s record has been unbroken for over 80 years now. Over the years, there have been contenders to the record, but none beating it just yet.