On 28 January 2011, despite interest from Rangers, Commons signed a three and a half-year deal with Celtic for a fee of around £300,000 and was given squad number 15. The following day, he made an immediate impact, scoring the opening goal on his debut in Celtic’s 4–1 League Cup semi-final win against Aberdeen with a lob from outside the box. On 6 February, Commons scored against Rangers in a Scottish Cup tie at Ibrox. The match ended 2–2. On his home debut at Celtic Park, he again scored against Rangers to add Celtic’s third goal. In his next home league game, Commons scored both goals, including a volley from 25 yards, as Celtic won 2–0 against Hamilton. Commons had now become an integral part of the Celtic side; playing just behind the main strikers, occasionally in a central role but more often fielded wide left.
On 9 April, Commons came off the bench to score the winning goal in a 1–0 SPL win over St Mirren. On 17 April, he scored from the penalty spot in Celtic’s 4–0 victory over Aberdeen in the Scottish Cup semi-final at Hampden Park, and then netted twice in a 4–0 league win against Kilmarnock at Rugby Park three days later. On 4 May, Commons notched yet another brace as Celtic lost 3–2 away to Inverness Caledonian Thistle. Five days later, Commons scored in a 2–0 victory against Kilmarnock with a 30-yard strike into the top right hand corner of the net. On 11 May, Commons scored the final goal of Celtic’s 3–0 win against Hearts. After scoring, he was sent off for the first time in his entire career after receiving a second yellow card for celebrating with the fans; resulting in him missing the last league game of the season through suspension. Commons picked up his first winner’s medal on 21 May when Celtic won the Scottish Cup, beating Motherwell 3–0. The opening goal was set up by Commons, who played a square pass to Ki Sung-Yeung which set up the Korean midfielder to score from distance with a powerful shot.
Commons began 2011–12 season as a regular in the Celtic team, but in their fourth league match of the season against St Johnstone, he missed an early penalty after slipping at the vital moment. Celtic ended up losing 0–1. As a result of missing the penalty, Manager Neil Lennon removed Commons as a penalty taker. On 2 October 2011, in the second half of Celtic’s 2–0 defeat against Hearts, Commons was shown a straight red card for a dangerous tackle. Commons was struggling to match the form he had shown the previous season and, also hampered by suspension and injuries, was no longer playing regularly. On 29 April 2012, Commons scored his first, and only, goal of the season in a 3–0 win over Rangers on 29 April 2012. Celtic finished the season as league champions, and Commons’ 24 league appearances saw him gain an SPL winner’s medal.
On 4 August 2012, Commons scored the only goal of the game as Celtic beat Aberdeen 1–0 in the opening game of the 2012–13 league season. In Celtic’s next league game on 18 August, Commons scored a last-minute equaliser to clinch a 1–1 draw against Ross County. On 21 August, Commons scored the opening goal in a 2–0 win against Helsingborgs in the Champions League play-off round first leg. Commons had now regained the form he had shown when he first joined Celtic in 2011. Manager Neil Lennon commented “Last season, Kris was curtailed by injuries and self-doubt, for whatever reason, I don’t know.”, but added regarding his current performances, “I think he is playing even better now than he was in his first season.” On 5 December, Commons scored the winning goal against Spartak Moscow from the penalty spot at Celtic Park, sending Celtic through to the last 16 of the Champions League for the first time in five years. On 16 March 2013 in the 4–3 home win over Aberdeen, Commons broke the record for the fastest goal in the SPL with a time of 12.2 seconds; a record previously held by Celtic teammate Anthony Stokes. Commons finished the season with both a League Championship winner’s medal and a Scottish Cup winner’s medal as Celtic completed a league and cup double.
Commons played in nine of Celtic’s opening ten fixtures of season 2013–14, scoring against Elfsborg and Shakhter Karagandy in Champions League qualifying ties and against Aberdeen in the league from the penalty-spot. He continued to play and score regularly, and hit a purple patch during December. On 1 December 2013, Commons scored a hat-trick at Tynecastle in a 7–0 rout of Hearts in the Scottish Cup. Five days later, he scored twice in a 5–0 league win away against Motherwell, the first of which he cleverly back-heeled an off-target Anthony Stokes shot past the Motherwell goalkeeper. On 21 December 2013, he scored again against Hearts, this time in a home 1–0 victory. Commons finished 2013 with another strike, the only goal in a 1–0 win away at Inverness CT on 29 December 2013. This impressive run of form saw Commons named the Scottish Premiership’s Player of the Month for December. Commons continued his goalscoring form into January, scoring twice in a 4–0 win away at St Mirren on 5 January 2014, the first of which was his 50th competitive goal for Celtic. Kris Commons finished the season as the top scorer in Scotland, netting 32 goals, and won both the PFA Scotland and Scottish Football Writers’ Player of the Year awards.
The arrival of new manager Ronny Deila in June 2014 saw Commons feature less regularly in the team. By January 2015, he had only started in around half of Celtic’s games in season 2014-15, and scored seven goals. However, amidst speculation over his future at Celtic, Commons began playing more regularly for the team. On 1 February 2015, he scored the second goal of Celtic’s 2–0 win over Rangers in the Scottish League Cup semi-final, which was the first Old Firm meeting since April 2012. On 5 February, Commons signed a two-year extension keeping him at the club until 2017. Commons said “I’m absolutely delighted to have signed this new contract with the club”, adding “I’ve loved my time at Celtic and this is where I want to continue playing my football.” On 15 March, Commons scored the opening goal in Celtic’s 2–0 win over Dundee United in the League Cup Final.