Earned Runs vs Unearned Runs

An earned run vs unearned run is a distinction made by the official scorer under MLB Rule 9.16. A run is earned if it scores because of a hit, walk, error, sacrifice, or any other action that advances a runner to a base. A run is unearned if it scores because of a base on balls, a balk, a passed ball, a wild pitch, or a runner being hit by a batted ball. The key: errors by the pitcher or fielders create earned runs; passed balls and wild pitches do not, those are unearned. If a runner reaches base on a passed ball, the scorer marks it unearned. If a runner reaches base on a wild pitch, that run is also unearned. Wild pitches still count as runs allowed, but they are not charged to the pitcher’s earned-run ledger. This single distinction changes a pitcher’s ERA by as much as 0.50 to 1.50 runs per game over a season, depending on how often the defense produces passed balls.

Errors, such as a dropped ball, a misplayed ground ball, or a failure to cover a base, result in earned runs. The pitcher’s own error also counts as earned, because it is an action that directly allows a runner to score. Passed balls are different. A passed ball occurs when a batted ball goes through or past a fielder who had a reasonable chance to field it. Under Rule 9.16, a run that scores on a passed ball is unearned. The same logic applies to wild pitches: a pitch that the catcher cannot handle and that allows a runner to advance is unearned. However, wild pitches do count in the runs allowed tally that feeds into ERA. The pitcher is still responsible for the out turn, but the run is marked unearned. This prevents a pitcher from being penalized for a defense that could not cleanly field the ball. The failure case: if a scorekeeper misclassifies a passed ball as an earned run, the pitcher’s ERA is artificially inflated by the number of passed-ball runners that scored. The correction is to review the official rulebook, which draws a clear line: if the ball was fieldable and the fielder missed it, the run is unearned.

Reconstruct the inning by listing every runner who reached base and determining the cause. Here are three scoring scenarios that show the difference.

Scenario 1: Clean Inning, No Errors

A pitcher records three outs. Every batted ball is fielded cleanly. No runners reach base. Earned runs: 0. ERA: 0.00 for that inning. This is the simplest case and rarely occurs in practice.

Scenario 2: Passed Ball Scores

A batter hits a ground ball to the left fielder. The ball skips past the fielder’s glove and rolls to the fence. The runner scores. The scorer judges the ball as fieldable, the fielder had a reasonable chance. The run is unearned. The pitcher’s earned-run count stays at 0 for that play. If this is the only run allowed in a 9-inning complete game, the pitcher’s ERA is (0 earned runs / 9 IP) × 9 = 0.00, even though one run scored. This is the scenario that frustrates fantasy players who rely on raw runs allowed.

Scenario 3: Error by the Pitcher

The pitcher drops a throw from the catcher while attempting to tag a runner advancing from third. The runner scores. The scorer marks this as an earned run because the error directly caused the run. If this is the only earned run in a 9-inning game, the ERA is (1 / 9) × 9 = 1.00. The pitcher’s own error lifts his ERA by 1.00 for that game.

Under MLB Rule 9.16, an earned run is any run that scores because of a hit, walk, error, sacrifice, or any other action that results in a runner advancing to a base. The standard is action-based: did the offense do something that produced the run, or did the defense fail to execute? An error by a fielder, such as a misplayed ball or a failure to cover a base, produces an earned run. A passed ball or wild pitch does not. The scorer’s judgment is subjective, and different scorekeepers can rule the same play differently. The authority gap: no rulebook tells a scorer how to decide whether a ball was “fieldable.” For high school games using NFHS rules, the scorer has even more discretion. The failure mode: if a scorer consistently rules passed balls as earned, a pitcher’s ERA can be 0.30 to 0.50 runs higher than it would be under a strict reading of Rule 9.16.

An unearned run under Rule 9.16 is one that scores because of a base on balls, a balk, a passed ball, a wild pitch, or a runner being hit by a batted ball. These runs are allowed but not earned. The rule is straightforward at first glance, but the definition of “passed ball” creates the most confusion. A passed ball is one that goes through or past a fielder who had a reasonable chance to field it. The scorer decides what “reasonable chance” means. For a fast ground ball that the fielder dives for and misses, most scorers rule it a passed ball. For a ball that the fielder simply drops, it is an error and the run is earned. The answer to “does a passed ball make a run unearned” is yes, always, if the scorer judges the ball as fieldable. If the ball was not fieldable, for example, a hard line drive that skips past the fielder before they can react, the run is earned because the defense did not have a reasonable chance. The failure case: scorekeepers who do not know this distinction will charge every run allowed, inflating the pitcher’s ERA.

When a pitcher commits an error that results in a run scoring, the scorer marks that run as earned. However, if that error occurs with two outs already recorded in the inning, the situation is different. Under Rule 9.16, once a pitcher records two outs in an inning and then makes an error that allows a runner to score, the scorer must judge whether the error was the direct cause. If the error occurred after two outs, the scorer typically marks the run as unearned because the pitcher had already earned two outs. This rule is designed to prevent a pitcher from being penalized for a single mistake that ends a near-complete inning. The practical effect: a pitcher who records two outs and then drops a ball on a throw to third sees that run marked unearned, lowering the ERA for that inning. The failure case: scorekeepers who do not apply this rule will charge the pitcher with an earned run, raising the ERA by as much as 1.00 for that game.

A relief pitcher who enters the game with inherited runners on base is not charged with those runners unless they score after the reliever enters. Under Rule 9.16, runs allowed are charged to the pitcher who allowed the runner to reach base, not to the reliever. If an inherited runner scores while the reliever is pitching, the run is charged to the starting pitcher, not the reliever. The reliever’s ERA is only affected by runs that score on their own pitches. This rule is essential for evaluating relievers, whose ERA is often inflated by inherited runners. The failure case: scorekeepers who charge the reliever with inherited runners produce an ERA that is 0.30 to 0.80 runs higher than the correct value. For relievers who pitch less than 30 innings, the inherited-runner effect can make a 3.00 ERA look like a 4.00 ERA. Use FIP or SIERA instead of raw ERA for relievers, because those stats ignore inherited-runner effects.

A team’s earned runs total is the sum of earned runs allowed by all pitchers on the team, plus inherited runners that score. A pitcher’s individual earned runs are only those that score while that pitcher is in the game and are judged earned under Rule 9.16. This distinction matters for team ERA calculations, which aggregate all earned runs across all pitchers. For example, a team that allows 50 earned runs over 200 innings has a team ERA of (50 / 200) × 9 = 2.25. But the starting pitcher may have allowed 15 of those runs, and the reliever only 5. The reliever’s individual ERA is lower, but the team ERA reflects the combined performance. The failure case: coaches who rely on team ERA to evaluate individual pitchers will misjudge relievers who enter with inherited runners. Team ERA is a team stat, not a pitcher stat.