The largemouth is marked by a series of dark, sometimes black, blotches forming a jagged horizontal stripe along each flank. The upper jaw (maxilla) of a largemouth bass extends beyond the rear margin of the orbit[7]. The largemouth is the largest of the black basses, reaching a maximum recorded overall length of 29.5 in/75 cm[8] and a maximum recorded weight of 25 pounds 1 ounce (11.4 kg).[8] The fish lives 16 years on average.

The juvenile largemouth bass consumes mostly small bait-fish, scuds, and insects. Adults consume smaller fish, crawfish (crayfish), frogs, snakes, salamanders, bats and even small water birds, mammals, and baby alligators.[10] In larger lakes and reservoirs, adult bass occupy deeper water than younger fish, and shift to a diet consisting almost entirely of smaller fish like shad, trout, ciscoes, shiners, and sunfish. Prey items can be as large as 25 to 35% of the bass's body length. Studies of prey utilization by largemouths show that in weedy waters, bass grow more slowly due to difficulty in acquiring prey. Less weed cover allows bass to more easily find and catch prey, but this consists of more open-water baitfish. Paradoxically, with little or no cover, bass can devastate the prey population and starve or get stunted. Fisheries managers need to take all these factors into consideration when designing regulations for specific bodies of water. Under overhead cover such as overhanging banks, brush, or submerged structure such as weedbeds, points, humps, ridges, and drop-offs, the largemouth bass will use its senses of hearing, sight, vibration, and smell to attack and seize its prey. It can sometimes hold up to 5 sunfish in its mouth. Adult largemouth generally are apex predators within their habitat, but they are preyed upon by many animals while young

Largemouth are keenly sought after by anglers and are noted for the excitement of their fight. The fish will often become airborne in their effort to throw the hook, but many say that their cousin species, the smallmouth bass, can beat them pound for pound. Anglers most often fish for largemouth bass with lures such as plastic worms (and other plastic baits), jigs, crankbaits and spinnerbaits. A recent trend is the use of large swimbaits to target trophy bass that often forage on juvenile rainbow trout in California. Live bait, such as nightcrawlers, minnows, frogs or crawfish, can also be productive. In fact, large golden shiners are one of the best things to use to catch trophy bass, especially when they are sluggish in the heat of summer time or in the cold of winter. Largemouth bass are known to take any bait it considers alive.[citation needed]

There is a strong cultural pressure among largemouth bass anglers which encourages the fish's live release, especially the larger specimens. Largemouth bass, if handled with care, respond well to catch and release; many studies have shown specimens which have survived being hooked and released multiple times.

The Largemouth Bass has been known to exist in many of the lower 48 states of the U.S. Although it is most popular in the southeastern states, many different varieties of the largemouth bass can be found in the north and western regions.[citation needed]

The International Game Fish Association (IGFA) officially recognizes the heaviest largemouth bass on record as having been caught by George Perry at Montgomery Lake in Telfair County, Georgia, on June 2, 1932. The fish weighed 10 kg (22¼ lb). A largemouth bass weighing 25 pounds 1 ounce was caught by Mac Weakley in Escondido, California's Dixon Lake on March 20, 2006, but Weakley inadvertently foul-hooked the fish and released it without submitting it for a IGFA record.[8]