What should I check before buying a used bat?

The mark your league takes

A metal bat must carry the mark your league names, printed on the bat; solid one-piece wood needs no mark.

USA Baseball says the bats it certifies carry a permanent certification mark on the barrel; temporary labels, stickers and decals are not allowed.

Decertified and withdrawn bats

USA Baseball buys approved bats in stores and tests them again, and a model that no longer meets its standard is decertified. A decertified bat is no longer approved in leagues that use the USABat standard, Little League, Babe Ruth and Cal Ripken, Dixie Youth and Dixie Boys, PONY, AABC and NABF among them, and one used in a game counts as an illegal bat under the league’s rules.

A decertification can cover one length of a model: USA Baseball’s list names the Easton Ghost X in its 30-inch, −10 length only, model numbers YBB18GX10 and LL18GHX, and every other length and drop of that bat stays approved, since each length and drop is certified on its own.

The full list of approved USA Baseball bats is at USABat.com.

USSSA keeps a list of bats that carried its mark but were later withdrawn by their maker or disallowed by USSSA, some in certain lengths and weights only. USSSA also withdraws any BBCOR bat the NCAA or the NFHS withdraws, and any USA Baseball bat that USA Baseball withdraws.

A BBCOR bat can be decertified too. In March 2020 the NFHS ruled the 33-inch Louisville Slugger Meta composite bat non-compliant in high-school play, after the Washington State University Sports Science Laboratory advised it that the bat had been decertified under BBCOR.

The NCAA and the NFHS keep an approved-for-play list of BBCOR bats. After more testing they took the 2020 Louisville Slugger Meta (−3) off it in its 33-inch, 30-ounce size only, and USSSA barred that bat too.

The size your player needs

Size a used bat as you would a new one: the fit gives the length and the drop for your player’s age, height, weight and league, and “Will this used bat work?”, linked below, holds a bat you’ve found up to them. Then check it with the bat in hand.

Stand the bat on its end beside the player, arm hanging: the knob should reach about the middle of the palm. Well past the wrist = too long; short of the palm = too short. Axe's variant: bat held against the center of the chest pointing out, fingertips should reach the knob.

Hold the bat by the knob, one hand, arm straight out from the shoulder, for 10 to 20 seconds. If the barrel dips or the arm shakes, the bat is too heavy: go one drop lighter at the same length, or one inch shorter at the same drop. Passing the test does not mean your player can go heavier.

Clubbie advice Who’s behind it?

Ask for clear photos of the mark and the model number printed on the bat before you go to see it. If the mark is worn off or hidden under tape, pass: an umpire has to be able to read it too.

In good light, run a hand along the barrel and look for cracks, dents and flat spots. Shake the bat gently by your ear: a rattle means something inside has come loose. Check that the end cap and the knob are tight, and that the grip isn’t hiding damage.

Bring your player along. A used bat is a bargain only if it’s the right size now, not one to grow into.