Schaub attended West Chester East High School in West Chester, Pennsylvania, where he lettered in football, basketball, and baseball.
Schaub enrolled at the University of Virginia in the fall of 1999, and began his career as a member of the Virginia Cavaliers football team. He redshirted his true freshman season. In 2000, starter Dan Ellis missed some time due to an injury, but fellow redshirt freshman Bryson Spinner received the bulk of playing time in relief. After the 2000 season, coach George Welsh retired and was replaced by Al Groh. Schaub was the starter for the first game of the 2001 season at Wisconsin. Over the 2001 season, Schaub and Spinner split quarterbacking duties nearly evenly. The two alternated in some games, while in others either Schaub or Spinner received nearly all the snaps. The two quarterback system worked relatively well with both effectively passing the ball to receiver Billy McMullen, the team's leading offensive threat.
Spinner transferred to the University of Richmond for the 2002 season, seemingly making Schaub the unquestioned starter. However, Schaub was briefly replaced by redshirt freshman Marques Hagans in the first game of the 2002 season against Colorado State University. Hagans was named the starter for the next game, against Florida State University, but was replaced by Schaub who went on to his breakout season. Schaub was the 2002 ACC Player of the Year, 2002 ACC Offensive Player of the Year and first-team All-State Virginia Sports Information Directors Association (VaSID) as a senior. Publicized in the 2003 preseason as a Heisman Trophy candidate, Schaub suffered a shoulder injury in the first game of the season and did not return for several games; therefore his overall numbers declined in his senior season. He was the Most Valuable Player of the 2003 Continental Tire Bowl and was twice selected to the All-ACC Academic Football Team. His University of Virginia awards included the John Acree Memorial Trophy, given to the football player with the highest qualities of leadership and unselfish service, and the Ben Wilson Award as the team’s most outstanding offensive player.
Schaub finished his college career with at least 22 school records. He played in a record 40 games at the quarterback position and finished his career as one of the most accurate passers in Atlantic Coast Conference history (.670 career completion percentage). His Virginia statistics included school career records for yards passing (7,502), touchdown passes (56), completions (716), attempts (1,069), completion percentage (.670), 300-yard games (8), and 200-yard games (20).
Schaub was selected by the Atlanta Falcons in the 3rd round of the 2004 NFL Draft as the 90th overall pick. He was the fifth of seventeen quarterbacks taken in a quarterback-rich class, including Eli Manning, Philip Rivers, and Ben Roethlisberger.
In 2004, Schaub played in 6 games with the Atlanta Falcons, including starting the week sixteen contest against the New Orleans Saints, replacing the injured Michael Vick.
In 2005, Schaub was named the Most Valuable Player in the American Bowl preseason game in Tokyo, Japan. In front of 45,203 fans at the Tokyo Dome, Schaub completed 11 of 13 passes for 117 yards and two touchdowns in a 27–21 comeback victory over the Indianapolis Colts. During the regular season he played QB in 5 games, starting one. His lone start came against the New England Patriots in week 5; Schaub threw for 298 yards and three touchdowns in the 31–28 loss. Schaub was the holder on extra points and field goals.
In 2006, Schaub again was the holder on extra points and field goals.
In March 8, 2007, the Houston Texans acquired Schaub from the Falcons for second-round picks in 2007 and 2008. As part of the deal, the teams also swapped first-round picks in 2007, exchanging the Falcons' 10th pick with the Texans' 8th pick. Schaub was introduced to his new team at a press conference on March 22, 2007, and the same day, the Texans released David Carr, opening the door for Schaub to become their long-term starter.
In each of the first two games of the 2007 season, Schaub threw for over 220 yards, a 71% completion percentage, and attained a quarterback rating of over 100; both games were victories for the Texans, winning 20–3 over the Kansas City Chiefs and 34–21 over the Carolina Panthers. The second victory marked the first 2–0 start in franchise history. In week four, he started against his former team, the Atlanta Falcons, in which he completed 28 of 40 attempts, with 317 yards, 1 touchdown, and no interceptions in what would be his second loss of the 2007 season.
Though Schaub was plagued with injuries throughout the 2007 season, he and backup quarterback Sage Rosenfels improved on the team's 2006 record of 6–10, bringing the Texans to their first .500 season in franchise history with an 8–8 record in the team's short history.
Schaub returned as the starter for the 2008 season. He didn't perform well in the first two games, losing to the Pittsburgh Steelers and Tennessee Titans but then had a great game against the Jacksonville Jaguars despite another loss. He sat out the week 5 loss to the Indianapolis Colts. In week 6, Schaub set the Texans franchise record for passing yards with 379 in a comeback win against the Miami Dolphins in which Schaub scored the winning touchdown on a quarterback draw with 3 seconds left. Schaub helped teammate wide receiver Andre Johnson lead the league in both receptions and receiving yards through week 8 of the season, having 56 catches for 772 yards. The new quarterback-receiver tandem had their best day together through mid-season during the week 8 matchup against the Cincinnati Bengals where Schaub threw for 280 yards, completing over 85% of his passes (24 of 28), 10 of those going to Johnson for 143 yards in the 35–6 rout. Schaub's season was broken up however with a knee injury against the Minnesota Vikings, which expected to keep him out for around 4 weeks, making Sage Rosenfels the new starter.
Against the Green Bay Packers, Schaub completed 28 of 42 pass attempts for 414 yards and 2 touchdowns, also leading the Texans down the field to set up a Kris Brown game-winning field goal. He played well down the stretch and the team finished 8–8 for the second consecutive season despite starting 0–4.
During the 2009 NFL season, Schaub led the Texans to a 9–7 record, the first winning record in team history. He led the league in passing yards (4,770), completions (396), yards per game (298), and passing attempts (583), while finishing fifth in touchdowns (29), compiling a quarterback rating of 98.6. He was selected to his first Pro Bowl as an injury replacement to Patriots quarterback Tom Brady, winning MVP honors.
There were high hopes for the Texans with the league's passing yards leader coming back for the 2010 year, but with the development of the running game, Schaub was only 9/17 for 107 yards for a touchdown and an interception in a Week 1 victory against the Indianapolis Colts. Hopes for strong start to the season were rejuvenated when Schaub threw for 497 yards in an overtime victory over the Washington Redskins on September 19, 2010. Schaub finished the season with 4370 passing yards, good for 4th in the league, but the team finished 6–10 and missed the playoffs.
In 2011, the Texans made numerous defensive improvements as Schaub led the Texans to its most successful season to date, helping guide his team part of the way to their first ever playoff appearance and clinching the first division title in Texans franchise history. Schaub started all 10 of the first regular season games, and while not on pace for one of his better seasons statistically, he helped his team reach a 7–3 record, the best start after 10 weeks in franchise history. After a week 10 game versus the Tampa Bay Buccaneers, Schaub was placed on IR with a Lisfranc injury to his right foot after a quarterback sneak. Schaub was initially replaced by Matt Leinart, who would go on to get knocked out for the season as well, leading to the eventual replacement by rookie T. J. Yates. The team finished 4–4 (including their playoff games) without Schaub as the starting quarterback.
Schaub entered the 2012 season in the final year of the contract he signed when he initially joined the Texans back in 2007.
After the season opening 30-10 win against the Miami Dolphins, Schaub signed a four-year, $62 million extension with the Texans, keeping him under contract through 2016.
During the week 3 game against the Denver Broncos, Schaub was illegally hit by Broncos defender Joe Mays and was thought to have lost part of his earlobe on the play, however he suffered only a laceration.
In week 11 against the Jacksonville Jaguars, Schaub threw for a career-high 527 yards and a career-high 5 touchdown passes in a 43–37 overtime victory for the Texans. Schaub's 527 yards is tied with Hall of Famer and former Houston Oilers quarterback Warren Moon for the second-most passing yards in a single game in NFL history, only behind Norm Van Brocklin's 554 yards passing in 1951 against the already defunct Boston Yanks.
In week 12, during the Thanksgiving game against the Detroit Lions, Schaub was kicked in the groin by Ndamukong Suh. Schaub rallied the Texans from a 10-point deficit to win once again in overtime, 34–31. After the game, Schaub said that he wouldn't want Suh on his team, calling him "not Houston Texan-worthy."
Along with Denver Broncos quarterback Peyton Manning, Indianapolis Colts quarterback Andrew Luck, and 8 of his Texans teammates, Schaub was invited to the 2013 Pro Bowl. The Texans were tied with the San Francisco 49ers for most players invited. The AFC team, of which the Texans were a part, lost decisively by a score of 62 to 35.
During the 2013 NFL Draft, the Texans upgraded Schaub's receiving weapons with the selection of DeAndre Hopkins in the first round.
Schaub began the season on Monday Night Football against the San Diego Chargers. Down 28–7 early in the 3rd quarter, Schaub led the largest comeback in Texans' franchise history with a 31–28 victory. Schaub finished the game 34/45 for 346 passing yards, three touchdowns, and an interception.
The next week against the Tennessee Titans, Schaub again had to rally the Texans to a comeback victory. He finished the day with 298 passing yards, three touchdowns (including the game-winner to rookie DeAndre Hopkins) and two interceptions in the Texans' 30–24 overtime victory.
The next two weeks (losses to both Baltimore and Seattle) saw Schaub throw three interceptions, including two 'pick-sixes' (interceptions returned for touchdowns on the runbacks). In the following week against the San Francisco 49ers, Schaub threw three interceptions, including a pick-six on his first pass attempt of the game. With that pick-six, Schaub had thrown a pick-six in four consecutive games, an NFL record. In Week 6 against the Rams, Schaub was injured during the game, but his replacement T. J. Yates threw another pick-6 to stretch the team total to five games. Despite recovering from an injured ankle, Schaub was benched in Week 7 in favor of Case Keenum. Keenum started for the remainder of the season until he suffered a thumb injury, and Schaub became the starter in Weeks 16 and 17. For the 2013 season, Schaub played in 10 games with 2,310 passing yards, 10 touchdowns, and 14 interceptions.
On March 21, 2014, the Oakland Raiders traded their 2014 sixth round draft pick to the Texans in exchange for Schaub. He was benched to start the season in favor of rookie QB Derek Carr.
On October 26, 2014, Schaub made his first pass attempt as a Raider in the regular season against the Cleveland Browns. It was a botched fake field goal that ended in an interception. Schaub was released by the team on March 16, 2015.
On March 31, 2015, Schaub signed with the Baltimore Ravens to be the back-up quarterback. His contract was for one-year, $2 million guaranteed and a $1 million signing bonus. Schaub was named the Ravens' starting quarterback for the rest of the 2015 season after Joe Flacco suffered a season-ending injury by tearing his ACL and MCL during a Week 11 victory over the St. Louis Rams. On December 13, after battling a chest injury, Schaub was replaced by Jimmy Clausen as the starter. Schaub finished his stint with the Ravens starting only two games with a 1–1 record, throwing 540 yards, three touchdowns, and four interceptions.
On March 8, 2016, Schaub signed a one-year contract with the Atlanta Falcons worth $2,750,000 with $500,000 guaranteed. Schaub backed up Matt Ryan in the Falcons' successful 2016 season. Schaub appeared in four games of 2016 with 16 passing yards. The Falcons eventually made it to Super Bowl LI, only to squander a 25-point lead and lose 28-34 in overtime to the New England Patriots.
On March 8, 2017, Schaub signed a two-year, $9 million contract extension with the Falcons.2× Pro Bowl selection (2009, 2012)
Pro Bowl MVP (2009)
NFL passing yards leader (2009)
4× AFC Offensive Player of the Week
Most Games Played at Quarterback – 90 (2007–2013)
Most Career Wins – 46 (2007–2013)
Most Career Pass Completions – 1,951 (2007–2013)
Most Pass Completions in a Single Season – 396 (2009)
Most Pass Completions in a Single Game – 43 (November 18, 2012 vs. Jacksonville Jaguars)
Most Career Pass Attempts – 3,020 (2007–2013)
Most Pass Attempts in a Single Season – 583 (2009)
Most Pass Attempts in a Game – 62 (12/13/10 vs. Baltimore Ravens)
Highest Completion Percentage, Career – 64.6 (2007–2013)
Most Career Passing Yards – 23,221 (2007–2013)
Most Passing Yards in a Single Season – 4,770 (2009)
Most Passing Yards in a Game – 527 (November 18, 2012 vs. Jacksonville Jaguars)
Most 4,000 passing yard seasons, career – 3
Most 3,000 passing yard seasons, career – 4
Most consecutive seasons, 4,000 yards passing – 2 (2009–2010)
Most consecutive seasons, 3,000 yards passing – 3 (2008–2010)
Most 400+ yard passing games, career – 4
Most 300+ yard passing games, career – 27
Most 300+ yard passing games, season – 9 (2009)
Most Consecutive Passing 300+ yard Games – 4 (2010)
Most Career Passing Touchdowns – 124 (2007–2013)
Most Passing Touchdowns in a Single Season – 29 (2009)
Most Career Interceptions – 78 (2007–2013)
Most Consecutive Games with an Interception returned for a Touchdown – 4 (2013)
Highest Passer Rating, Career – 90.9 (2007–2013)
Highest Passer Rating in a Single Season – 98.6 (2009)
Most Career 4th Quarter Comeback Wins – 11 (2007–2013)
Most 4th Quarter Comeback Wins in a Single Season – 2 (5 times) (tied with David Carr)
Most Career Game Winning Drives – 14 (2007–2013)
Most Game Winning Drives in a Single Season – 4 (2009)