UTERTo tell largemouth, smallmouth and spotted bass apart, close the fish's mouth and look at the jaw. A largemouth's upper jaw runs past the back of the eye. Smallmouth and spotted bass jaws stop at or before it. Then look at the sides: vertical bars mean smallmouth, while rows of small spots below a blotchy stripe, plus a rough patch on the tongue, mean spotted bass.
Those three checks (jaw, pattern, tongue) settle almost every fish in under 30 seconds. Color is the weakest clue, because all three bass change shade with the water they live in.
Quick-ID table
| Feature | Largemouth | Smallmouth | Spotted bass |
|---|---|---|---|
| Upper jaw (mouth closed) | Extends past the back of the eye | Stops at or before the back of the eye | Stops at or before the back of the eye |
| Side pattern | One dark, fairly solid horizontal stripe | Vertical bars or blotches, no solid stripe | Broken, blotchy stripe with rows of small dark spots on the lower sides |
| Tongue | Usually no tooth patch | Usually no tooth patch | Usually a rough tooth patch |
| Dorsal fins | Deep notch, almost two separate fins | Joined, shallow notch | Joined, shallow notch |
| Color | Green to olive, darker on top | Bronze to brownish-green | Olive-green, lighter sides |
| Scales | Smooth to the touch | Fairly smooth | Feel rougher than a largemouth's |
| Typical water | Weedy, warm, slower water; ponds, lakes, grass | Clear, cooler water with rock and current | Clear reservoirs with rock and clay; deeper than largemouth |
Based on the North Carolina Wildlife Resources Commission's black bass ID chart and TPWD's bass identification page, both linked below.
Check 1: the jaw
This is the most reliable single feature, and both TPWD and NC Wildlife lead with it. Hold the fish with its mouth fully closed, look at the corner of the mouth, and imagine a vertical line down from the back edge of the eye.
- Largemouth: the jaw goes well past that line. That's where the "largemouth" name comes from.
- Smallmouth and spotted: the jaw ends at the line or before it.
Check it with the mouth closed. With the mouth open and the jaw dropped, every bass looks like it has a big mouth.
Check 2: the side pattern
Largemouth: one stripe
A largemouth has one dark horizontal band from the gill to the tail. In clear water it's crisp. In stained water it fades to a row of dark blotches. Below the stripe, the belly is clean and pale.
Smallmouth: vertical bars
Smallmouth are bronze to brownish-green with vertical bars or blotches down the sides, and often bars radiating back from the eye. There's no solid horizontal stripe. The bars can fade when a fish has been in the livewell, so look right after landing it.
Spotted bass: the spots below the line
The name gives it away. Below a broken, blotchy lateral stripe, a spotted bass has neat rows of small dark spots along its lower sides, scale by scale, like dotted lines toward the belly. A largemouth's lower sides are plain. NC Wildlife also notes the spotted bass stripe is more solid just in front of the tail.
Check 3: the tongue
If the jaw and pattern don't settle it, which mostly happens with spotted bass against small largemouth, wet a finger and run it lightly over the fish's tongue. Spotted bass usually have a small rough patch of teeth there that feels like fine sandpaper. Largemouth and smallmouth usually don't.
"Usually" matters. Use the tongue patch to confirm, not as your only check.
Bonus check: the dorsal fin
Look at the top fin. On a largemouth, the notch between the spiny front dorsal and the soft rear dorsal is deep, so they look nearly like two fins. On smallmouth and spotted bass, the two parts are clearly joined. NC Wildlife calls the largemouth notch "deeper than on other bass species."
Where you'll find each one
Location narrows the list, but all three can live in the same reservoir.
- Largemouth are in every Lower 48 state and Hawaii. They prefer grass, wood, docks and warmer, slower water. Largemouth bass by region.
- Smallmouth run from the Tennessee Valley and the Ozarks north through the Great Lakes and Northeast, and west to the Columbia, Snake and John Day rivers. Look on rock, gravel and current. Examples from our calendar: Dale Hollow and Pickwick in winter, the Susquehanna and New River in summer, and Lake Erie and Lake St. Clair. Smallmouth bass by region.
- Spotted bass are in the Southeast and lower Midwest, from Georgia and Alabama to Kentucky, Missouri, Texas and Oklahoma, plus California reservoirs like Bullards Bar and Oroville, which grow very big spots. They often hold deeper than largemouth on clear lakes, on rock, clay points and standing timber. Spotted bass by region.
On a lake like Lanier or the Coosa chain, you can catch all three on one point in one afternoon. See Georgia spotted bass and Alabama spotted bass.
Look-alikes worth knowing
Alabama bass
Alabama bass were long counted as a type of spotted bass and are now treated as their own species. They look very much like spotted bass, with the same short jaw, tongue patch and rows of spots. NC Wildlife's chart says the stripe near the tail is more blotchy on an Alabama bass and more solid on a spotted bass. NC lists Alabama bass as invasive. If you catch one outside its native range, report it to your state agency.
Guadalupe bass
The state fish of Texas, found in Hill Country rivers like the Llano, Pedernales, Blanco and San Marcos. Like a spotted bass, it has a short jaw and rows of spots, but it's smaller, with diamond-shaped blotches along the sides. TPWD groups it with the spotted bass on its ID page. Texas Guadalupe bass.
Shoal bass and redeye bass
River bass of the Southeast, mostly Georgia, Alabama and Florida's Apalachicola system. Shoal bass have bold vertical blotches and look like a smallmouth with a stripe. Redeye bass and their relatives, such as Bartram's bass in the Carolinas, often have red eyes and white or orange edges on the tail and fins. All have short jaws. See shoal bass and redeye bass.
Hybrids
Where smallmouth and spotted bass, or spotted and largemouth, share a lake, hybrids happen and some fish won't fit any box. If the jaw says one thing and the pattern says another, you may have one.
Why the ID matters
Some states set different size and bag limits for each black bass, and some lakes have their own rules. A short spotted bass can be legal to keep where a short largemouth isn't, or the other way round. Check your state agency before you keep one, for example Georgia DNR, Alabama ADCNR or TPWD. Rules change, so look them up each season.
Spawning differs too: smallmouth and spotted bass bed on gravel, rock and clay, often deeper than largemouth. See when bass spawn, state by state.
Still not sure? Snap a photo
Fish Scouter's Fish ID takes one photo and returns up to three likely species. It uses your water and the month as a hint, and points to the marks that separate them. Every match opens that fish's page, its season calendar for your area and a catch log. Use it as a second opinion next to the jaw check. Try Fish Scouter free and log your next bass.