Carroll started his professional career with Newcastle United in 2006. He spent a small time on loan with Preston North End. He scored his first league goal there. He became as a regular in the Newcastle first team by 2008. When Newcastle got relegated from the Premier League to the Championship in 2009, he scored 17 goals in 39 appearances. Newcastle finished first in the Championship in that season. They earned automatic promotion back to the Premier League as a result. Caroll played for Newcastle in the Premier League again. He played 19 times and scored 11 goals.
Carroll signed for Liverpool on the last day of the transfer window on 31 January 2011. The transfer fee was £35 million. It was the highest amount ever paid by one club to another for a British footballer at that time. Carroll was bought to replace Fernando Torres. Torres had moved from Liverpool to Chelsea on the same day for a fee of £50 million. He suffered an injury in December. Therefore, he could not debut for Liverpool until March 2011. He scored his first two goals for his new club in April 2011 in a 3–0 victory over Manchester City. In August 2012, Liverpool agreed a £2 million loan deal with West Ham. It was a season-long loan. West Ham permanently signed him in June 2013. They paid a fee of £15 million.
Carroll started his youth career in Newcastle United. He scored some goals for the reserve team. He made his first-team debut on 2 November 2006. He was 17 years and 300 days old then. This was in a 1–0 UEFA Cup win over Palermo. He came on as a late substitute for Nolberto Solano. In doing so, he became the youngest ever player to represent Newcastle in Europe.
He made his FA Cup debut on 17 January 2007. Here too, he appeared as substitute for the last ten minutes. Birmingham City beat Newcastle 5-1 in that match. On 25 February 2007, Carroll made his Premier League debut for Newcastle. He came on as a substitute in the 87th minute in the 1–0 defeat by Wigan Athletic. He had a shot on target in this match. A good save from Wigan goalkeeper John Filan prevented him from scoring his first Newcastle goal.
In 2007, he was the recipient of the "Wor Jackie Milburn Trophy". This is awarded every year to the rising star of North East England football.
On 29 July 2007, Carroll scored his first senior goal in a 2–0 win over Juventus. This was a friendly match. He scored the goal with his left foot. After the game, Italian goalkeeper Gianluigi Buffon praised Carroll. Buffon said Carroll had a great future.
On 14 August 2007, Carroll began a six-month loan with Preston North End. He made his debut for them in the League Cup against Morecambe on the same day. Carroll was sent off playing for Preston against Scunthorpe United on 18 September. He scored his first Championship goal, and his first English league goal, against Leicester City on 6 November.
Carroll made his first appearance for Newcastle in the 2008–09 season on 20 October. He came on as a substitute for Shola Ameobi at home to Manchester City. Carroll was in the starting team against West Ham United at home on 10 January 2009. He scored his first goal at home in this match. It was a header. The match ended as a 2-2 draw. He signed a new three-and-a-half-year contract on 12 March 2009. His contract at Newcastle now ended in 2012.
Newcastle got relegated that season. First team strikers, Michael Owen, Mark Viduka and Obafemi Martins left the club. Carroll joined Shola Ameobi in attack for Newcastle at the start of the new season. His first league goal in the Championship came on 16 September 2009 against Blackpool with a header. By 2010 Carroll was playing almost every game. He had a new strike partner, Peter Løvenkrands. These two players scored more than half of the club's goals in 2010. Carroll finished the season as Newcastle's top scorer. He had 19 goals in all competitions. 17 were in the league, 2 in cup games.
Carroll was given squad number 9 for the 2010–11 season. This number is important for Newcastle United supporters. Great strikers like Jackie Milburn, Malcolm Macdonald and Alan Shearer have worn this squad number for Newcastle. Carroll scored his first career hat-trick against Aston Villa in the their 6–0 win in the Premier League on 22 August 2010. Carroll came on as a substitute for Kevin Nolan against Manchester City. He captained the team for the first time in this match. In October 2010, Carroll signed a new five-year contract. His contract lasted till 2015. Carroll scored Newcastle's third goal in a 3–1 victory over Liverpool at St. James' Park on 11 December 2010. It was a shot from 25-yards out. The shot was a low drive.
On 31 January 2011, Liverpool bid £30 million for Carroll. This was rejected. Newcastle then accepted a bid of £35 million. Carroll passed a medical and signed a contract soon. The transfer was completed shortly before the 11.00pm deadline. Carroll said he had been forced to leave Newcastle. But the club said he had requested a transfer after they turned down Liverpool's £30 million bid. Liverpool confirmed that Carroll would wear the number 9 jersey. This was previously worn by Fernando Torres, who left Anfield for Chelsea on the same evening for £50 million. The transfer made Carroll the eighth overall most expensive footballer at the time. He was the most expensive British footballer of all time. He also became the second most expensive footballer playing for a British club, after Torres. Carroll had suffered an injury while with Newcastle United. Therefore, Liverpool announded Carroll would have to wait some time before his debut.
He finally made his Liverpool debut as a substitute in the 3–1 win against Manchester United on 6 March 2011. On 10 March, he appeared in his first European game for Liverpool. Liverpool lost the match 1-0 to Braga in the Europa League. Carroll came as a substitute after half-time. In the return leg a week later, he made his first Liverpool start. The game finished 0–0. Liverpool left the competition because they had lost 1-0 on aggregate. On 20 March, he made his first Premier League start for Liverpool against Sunderland. He did not score. Liverpool won the game 2-0. On 11 April, Carroll scored his first goals for Liverpool. This was in a 3–0 victory against Manchester City at Anfield. His first goal was from long-range. His second was a header. He played several more times that season. But, he did not score any more goals.