One of the most regular World Series participants in history, he appeared in ten of them, winning four, and ranks among Series career leaders in several categories. He also won two World Series as a coach. His lifetime slugging average of .427 ranked fourth among AL catchers at the time of his retirement.
Howard was born in St. Louis, Missouri to Travis Howard and Emaline Hill, a nurse at a local hospital. At the age of six, his parents divorced and his mother remarried. Howard was a standout athlete at Vashon High School.
Howard made the Yankees' major league roster at the start of the 1955 season. On April 14, 1955, the second game of the season, Howard made his major league debut, entering the game as a left fielder in the sixth inning. Howard hit a single in his only plate appearance of the day. He became the first African American to play for the Yankees. Howard was known to be very slow afoot. This caused Casey Stengel, the Yankees' manager, to say, "Well, when they finally get me a nigger, I get the only one who can't run." When Howard first came to the Yankees, Stengel referred to him as "Eightball". Howard made his first start on April 28, as it was difficult to find room for Howard in the lineup; Berra won his third MVP award in 1955, and Mickey Mantle and Hank Bauer were solid outfield regulars. Stengel used Howard as a backup catcher and occasional outfielder, competing for playing time with Norm Siebern and Enos Slaughter. He hit .290 with 10 home runs and 43 runs batted in (RBIs) in 97 games played for the season.
In the 1955 World Series against the Brooklyn Dodgers, Howard hit a home run in his first at bat, off Don Newcombe in the second inning of Game 1, which tied the game 2-2; the Yankees won 6-5, but it was Howard's ground ball out to Pee Wee Reese in Game 7 which ended the Series, the first time in six meetings that the Yankees lost to Brooklyn. In the 1956 World Series against Brooklyn he played only in Game 7, but his solo home run off Newcombe in the fourth inning was one of four Yankee HRs in the 9-0 victory. Against the Milwaukee Braves in the 1957 World Series, his three-run homer off Warren Spahn with two outs in the ninth inning of Game 4 tied the score 4-4, though Milwaukee won 7-5 in the 10th inning. As the Yankees again met the Braves in the 1958 World Series, his impact did not become notable until Game 5, when he caught Red Schoendienst's sinking fly ball in the sixth inning and made a throw to catch Bill Bruton off first base for a double play, preserving a 1-0 lead. In Game 6, he threw Andy Pafko out at the plate in the second inning, and singled and scored with two out in the tenth inning for a 4-2 Yankee lead; the run proved decisive, as the Braves came back to score once in the bottom of the frame. In Game 7, his two-out RBI single scored Berra for a 3-2 lead in the eighth inning, with New York going on to a 6-2 win, completing only the second comeback by a team from a 3-1 deficit in a Series. Howard was later given the Babe Ruth Award, presented by the New York chapter of the Baseball Writers' Association of America, as the top player in the Series, although the World Series MVP Award was won by teammate Bob Turley.
By 1959, Howard was often playing at first base in order to remain in the lineup. Despite not finding a regular position yet, he was first selected to the All-Star team in 1957, the first of nine consecutive years through 1965 in which he made the squad; he would appear in six of the games (1960 to 1964), including both 1961 contests.
In 1960, Howard finally took over the majority of the catching duties from Berra, although his .245 batting average was his lowest to date. The Yankees met the Pittsburgh Pirates in the 1960 World Series, and Howard's two-run pinch-hit homer off Roy Face in the ninth inning of Game 1 brought the Yankees within two runs, though they lost 6-4. Howard hit .462 in the Series, but did not play in Game 7 after being hit on the hand by a pitch in the second inning of Game 6, and could only watch as the Pirates won the Series, 10-9, on Bill Mazeroski's home run leading off the bottom of the ninth. In 1961 he raised his average 103 points to a career-best .348 mark on a team that featured Roger Maris' record 61-home run season; Howard also enjoyed his first 20-homer campaign, along with 77 RBI, as the Yankees set a major league record with 240 HRs. He finished tenth in the MVP voting that year, won by Maris. Meeting the Cincinnati Reds in the 1961 Series, he and Bill Skowron had solo home runs in the 2-0 Game 1 victory, and he scored three runs in the final 13-5 win in Game 5. He followed up with a 1962 season in which he batted .279 with a career-best 91 RBI, again hitting over 20 homers, and collecting eight RBI in an August 19 game in Kansas City which the Yankees won, 21-7. Although Howard batted only .143 in the 1962 World Series against the San Francisco Giants, the Yankees won in seven games.
In his 1963 MVP season, he batted .287 with 28 home runs, 85 RBI and a .528 slugging average, also winning his first Gold Glove. The Yankees were swept by the Los Angeles Dodgers in the 1963 Series, though Howard hit .333 and drove in the only Yankee run of Game 2. He batted .313 (just ten points behind batting champion Tony Oliva) with 84 RBI in 1964, again winning the Gold Glove and placing third in the MVP vote as Berra took over Ralph Houk's post as manager. His totals of 939 putouts and 1,008 total chances broke the AL records of 872 and 963 set by Earl Battey with the 1962 Minnesota Twins; Bill Freehan would top Howard's marks with the 1967 Detroit Tigers. Howard also led the AL in fielding average in 1964 with a .998 mark. Playing in his ninth World Series in ten years against the St. Louis Cardinals, he batted .292 though the Yankees were overcome in seven games; he tied a Series record with three passed balls, including two in the 9-5 Game 1 loss. In 1965, Howard injured his elbow during spring training. He played in four games through April, and then had surgery, missing five more weeks.
Howard struggled in 1967. Backing up Jake Gibbs, Howard batted only .198 through the start of August. On August 3, 1967, Howard was traded to the Boston Red Sox for Pete Magrini and a player to be named later (Ron Klimkowski). Though he batted only .147 for Boston, he was effective in handling the pitchers; teammate Tony Conigliaro noted, "I don't think I ever saw a pitcher shake off one of his signs. They had too much respect for him." In 1967, Howard also took over Sherm Lollar's major-league record for career fielding average; Freehan moved ahead of him in 1973. Howard had his last postseason highlight in the 1967 World Series against the Cardinals when his bases-loaded single in the ninth inning of Game 5 drove in two runs for a 3-0 lead. The hit was crucial, as former teammate Maris homered in the bottom of the inning for the Cardinals before the Red Sox closed out the 3-1 win. St. Louis, however, won the Series in seven games. It was the sixth losing World Series team Howard played on; he and Pee Wee Reese have the dubious distinction for playing on the most losing World Series teams.
On October 29, 1968, Howard was released by the Red Sox. Over his 14-year career, he batted .274 with 167 home runs, 1,471 hits, 762 RBI, 619 runs, 218 doubles, 50 triples and nine stolen bases in 1,605 games. His .427 slugging average trailed those of only Dickey (.486), Berra (.482) and Mickey Cochrane (.478) among AL catchers. His 54 total World Series games placed him behind only teammates Berra and Mantle. Howard is also credited with being the first to use the extended index and pinky finger (corna) to indicate that there were two out in the inning, this being more visible to teammates in the outfield than the usual "two" gesture of the index and middle fingers.
The next year he returned to the Yankees, where he served as first-base coach from 1969 to 1979. He was the first black coach in the American League. The team became World Series champions in 1977 and 1978 and AL champions in 1976. In 1977 during a game against the Boston Red Sox at Fenway Park, Howard and Yogi Berra were peacemakers during a dugout incident between Yankees player Reggie Jackson and Yankees manager Billy Martin.
In Howard's memory, the Yankees wore black armbands on their sleeve during the 1981 season. On July 21, 1984, the Yankees retired Howard's uniform number 32 and dedicated a plaque in his honor for Monument Park at Yankee Stadium. On that day the Yankees also gave the same honors to Maris who, unlike Howard, was still living. Howard's plaque describes him as "A man of great gentleness and dignity" and "one of the truly great Yankees."
Howard is credited with inventing the batting "donut", a circular lead weight with a rubber shell used by waiting batters in the on-deck circle by placing it around a bat to make it feel heavier, so that the bat will feel lighter at the plate and easier to swing. Its widespread use caused the discontinuation of the practice of hitters swinging multiple bats at the same time while waiting to hit. Howard helped two New Jersey entrepreneurs, Frank Hamilton and Vince Salvucci, to market the bat weight and lent his name to the product.