He finished fourth in the championship with two wins, two pole positions and three fastest laps, and earned the Rookie of the Year award.
He also demonstrated strong form in the international F3 rounds, with second place at the Macau Grand Prix and fourth place at the Zandvoort Marlboro Masters.
The Finn stayed in World Series by Nissan for 2004 but moved to the Pons team and won the championship ahead of Tiago Monteiro, with 192 points and six wins.
Kovalainen competed in the 2004 Race of Champions at the Stade de France in Paris. He became the first non-rally driver to win the Henri Toivonen Memorial Trophy and earn the title "Champion of Champions", beating World Rally Champion Sébastien Loeb in the finals. He also participated in the Nations' Cup alongside countryman Marcus Grönholm. Their team finished in second place after Kovalainen's Ferrari 360 Modena broke down in the finals, ironically, losing to Loeb and the French team. Kovalainen's feat included winning over Loeb in a WRC car, although he had never even sat in a rally car before, and over the Ferrari Formula One star Michael Schumacher in a Ferrari 360 Modena.
| Round | Opponent | Car | Time | Difference | Result |
|---|---|---|---|---|---|
| 1 | David Coulthard | Race of Champions Buggy | 1:45.8988 | -11.905 | 1 - 0 |
| 2 | Jean Alesi | Ferrari 360 Modena | 1:48.9325 | -1.7085 | 1 - 0 |
| Semi-Finals | Michael Schumacher | Ferrari 360 Modena | 1:45.3851 | -10.9954 | 1 - 0 |
| Final | Sébastien Loeb | Peugeot 307 WRC | 1:42.2602 | -0.7977 | 1 - 0 |
| Sébastien Loeb | Ferrari 360 Modena | 1:47.4383 | -8.1459 | 2 - 0 |
He returned to the Race of Champions in 2005, but was knocked out in the semi-finals by Tom Kristensen.
Kovalainen made another impact in the Race of Champions in 2006, winning the Nations Cup together with his fellow Finnish driver Marcus Grönholm; despite this, he was again eliminated in the semi-finals by Mattias Ekström by a mere 0.0002 seconds.
In 2007, Kovalainen was strong again. He and his partner, Marcus Gronholm, carried Finland to the final of the nations cup, where the strong German pairing of Michael Schumacher and Sebastien Vettel beat them. Kovalainen beat Vettel in the individual race, before crashing right on the line in the next round. He crossed the line out of control, and Andy Priaulx pipped him. Kovalainen probably would have won had he not crashed.
Kovalainen, Franck Montagny and José María López tested the Renault R23B F1 car at Barcelona in December 2003. Kovalainen also tested for Minardi, but Renault made him second test driver alongside Montagny.
Kovalainen was promoted in Montagny's place at the end of and spent the season in a full-time testing role, logging over 23,000 km of testing.
Renault's lead driver Fernando Alonso had signed for McLaren for the 2007 season, and Renault elected to promote Kovalainen in his place, which they confirmed on September 6, 2006. Team boss Flavio Briatore said: "With Kovalainen, I hope to find the anti-Alonso."
Kovalainen made his race debut in at the 2007 Australian Grand Prix driving for Renault. His performance was a huge disappointment; he made several mistakes during the race and finished 10th. Flavio Briatore told the press after the race that it was a disappointing debut for the young Finn. He said that hopefully the real Heikki will show up next time.
Kovalainen scored his first World Championship point in his second Grand Prix at Sepang, Malaysia, and followed this with a disappointing race in Bahrain. He then secured seventh place in Barcelona, outperforming team mate Giancarlo Fisichella. He was well down the order in Monte Carlo and never looked like a points finish was a possibility. However, he came back strongly and finished in the points again in both North American races.
During the Canadian GP, he made mistakes throughout practice, including one at the exit of turn 7, and hit the barrier, which was reminiscent of Jacques Villeneuve. He crashed at the first chicane in qualifying, and damaged his rear wing significantly, and failed to make it through to the second session. He made progress early on, and then halted. He seemed to have a lot of luck with the strategy, and every time the safety car came out it was beneficial to him. A podium was within his grasp, but he could not find a way past Alexander Wurz of the Williams, who also started towards the rear of the pack. Kovalainen was pulling away from fellow Finn Kimi Räikkönen in his Ferrari in the closing stages, which was a real confidence booster for the team.
In the United States GP at Indianapolis Motor Speedway, he also looked impressive. He qualified well, and a good start saw him go past Räikkönen to go into fifth place. He held Räikkönen off, and led the race at the end of his first stint because those cars ahead of him had already made their pit stops. He re-joined behind the Ferrari, but looked comfortable in sixth place until Nick Heidfeld's BMW Sauber broke down in front of him, and Kovalainen took over Heidfeld's fifth place. He stayed there until the chequered flag, and team-mate Fisichella failed to score points.
The second half of the European season failed to produce such strong results, but it did keep the points tally ticking over. During the French GP at Magny-Cours, there would be disappointment. He was with his team mate until the sharp Adelaide hairpin, where Jarno Trulli's Toyota made an optimistic lunge up the inside of Kovalainen which wrecked both drivers' races. Kovalainen had to go back to the pits for some repair work and subsequently overtook just a few backmarkers. Seventh place at the British GP was no disaster, seeing as he beat Fisichella. The Nürburgring only gave Kovalainen a point, although a better strategy may have seen him on the podium. The Hungaroring only brought him one point, although Istanbul Park netted three, with Kovalainen coming ahead of Robert Kubica. Kovalainen led the Grand Prix there for a while, when those ahead of him outright pitted earlier than him. Seventh place at Monza was a fair result. The team took a gamble at the next race in the Spa-Francorchamps, with Kovalainen on a one stop strategy when his challengers for the rear end of the points were all on two stop strategies, which included the BMW's of Heidfeld and Kubica (who was sent ten places down the grid due to an engine change), Nico Rosberg and Mark Webber. A good start from Kovalainen saw him become a mobile chicane for all of these except Webber. The gamble did not pay off, although Kovalainen held off Kubica in the closing stages to secure the final points position. Better was to come at the Japanese GP at Fuji Speedway, where, despite not making it through to the final qualifying session, Kovalainen raced well. While most of his rivals got into trouble in one way or another, Kovalainen did not and held off Kimi Räikkönen to take second place and his first podium in Formula One.
On 14 December 2007, it was confirmed that Kovalainen would drive the second car for McLaren Mercedes for the 2008 Formula One season alongside Lewis Hamilton. Kovalainen is the fourth Finn to race for the Woking based team, following Keke Rosberg, Mika Häkkinen and Kimi Räikkönen, all of whom have won the World Championship, albeit Mika Häkkinen being the only Finn to win the World Championship in a McLaren car. Kovalainen began his first official testing session with McLaren on January 9 2008 with Pedro de la Rosa at Jerez, and continued the next day with Lewis Hamilton. Kovalainen's best laptime was 1:19.752, losing to Hamilton only by 0.061 seconds. On the third day of Valencia testing Kovalainen posted the fastest lap of the day with 1:11.000, a new lap record on the Valencia track for a V8 engine. On the third day of Jerez testing Kovalainen posted the fastest lap of the day with 1:17.974, a new lap record on the Jerez track for a V8 engine. In his first race at the 2008 Australian Grand Prix he was the quickest in Q1 and started 3rd on the grid behind Lewis Hamilton and Robert Kubica. A safety car situation prevented Kovalainen from finishing in second place behind team-mate Lewis Hamilton. He ended the race in fifth, after accidentally pressing the pit lane limiter on the final lap and granting fourth place to Fernando Alonso. In Malaysia, he set the 3rd fastest time of Q3, but was moved back 5 places for blocking Nick Heidfeld's BMW Sauber in the latter stages of the session. He finished the race 3rd with help from team mate Lewis Hamilton's problem in the pits, and Ferrari's Felipe Massa retiring due to a spin. In the next race in Bahrain, Kovalainen was well off the pace of the Ferraris and the BMW Saubers and came home 5th.
At the 2008 Spanish Grand Prix on 27 April 2008, Kovalainen was leading on lap 22, when his car crashed into the tyre wall. The crash was very reminiscent to Lewis Hamilton's crash the previous year at the Nürburgring, with a similar looking tyre failure. Kovalainen's car was almost completely buried under the tyres, which consisted of five rows. In previous years, the same position only had three rows of tyres. Additional two rows were added for the 2008 race by Paco "Paquillo" Mora, who is responsible for the maintenance of the track. This possibly saved Kovalainen from hitting the wall, thus preventing a possible serious injury. He waited in his car as marshals removed it from the track. The safety car was deployed for six laps as the debris was removed, and he was finally removed from the car and placed in a stretcher, at which point he gave a "thumbs-up", the first sign of life for over 10 minutes. He was then taken by helicopter to a Barcelona area hospital for further tests. His final condition was a minor concussion, whilst also complaining of a sore elbow and neck. He was released from the hospital the next day and was able to race in the Turkish Grand Prix, two weeks later.
In Turkey, Kovalainen put his car on the front row of the grid in second place, but suffered a puncture and dropped back. He would finish that race a lowly 12th. More disappointment was to follow in Monaco as he stalled his car on the grid and had to start from the pitlane. He made his way up to 8th place and the final point scoring position. In Montreal, he was unimpressive in qualifying and was compromised by staying out when most rivals pitted during the safety car period. Despite many retirements and problems occurring between those ahead of him, he would not get it in the points, finishing in 9th place. After the Canadian Grand Prix, Kovalainen was 6th in the championship standings with 15 points - equal with Red Bull Racing's Mark Webber. At the 2008 British Grand Prix, Kovalainen started his weekend by setting the second fastest time in Fridays free practice session. On the next day, Kovalainen topped the timesheets. Later on Saturday during qualifying, Kovalainen achieved his maiden pole position, beating Red Bull's Mark Webber by 0.505 seconds, with fellow Finn Kimi Räikkönen managing third.
In the week leading up to the 2008 Hungarian Grand Prix, McLaren confirmed that Kovalainen will remain with the team for .
He won his first Grand Prix at Hungary in 2008, becoming the 100th different driver to win a Formula One Grand Prix.
Kovalainen has a British girlfriend Catherine Hyde who studies sports psychology. They have decided to get married on October 10 2010.
| Season | Series | Team Name | Races | Poles | Wins | Points | Final Placing |
| 2001 | British Formula Renault | Fortec Motorsport | 13 | 2 | 2 | 253 | 4th |
| 2002 | British Formula 3 | Fortec Motorsport | 26 | 2 | 5 | 257 | 3rd |
| 2003 | World Series by Nissan | Gabord Competicion | 18 | 3 | 1 | 134 | 2nd |
| 2004 | World Series by Nissan | Pons Racing | 18 | 10 | 6 | 176 | 1st |
| 2005 | GP2 Series | Arden International | 23 | 2 | 5 | 105 | 2nd |
| 2007 | Formula One | Renault F1 | 17 | 0 | 0 | 30 | 7th |
| 2008 | Formula One | Vodafone McLaren Mercedes | 15 | 1 | 1 | 51* | 6th* |
| Year | Entrant | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | DC | Points |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2005 | Arden International | SMR FEA 1 | SMR SPR 3 | ESP FEA 3 | ESP SPR Ret | MON FEA 5 | EUR FEA 1 | EUR SPR Ret | FRA FEA 1 | FRA SPR 3 | GBR FEA 2 | GBR SPR 3 | GER FEA 5 | GER SPR 6 | HUN FEA 2 | HUN SPR 5 | TUR FEA 10 | TUR SPR 1 | ITA FEA 1 | ITA SPR 5 | BEL FEA 15 | BEL SPR 9 | BHR FEA 3 | BHR SPR Ret | 2nd | 105 |
| Year | Entrant | Chassis | Engine | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | WDC | Points |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2007 | ING Renault F1 Team | Renault R27 | Renault RS27 2.4 V8 | AUS 10 | MAL 8 | BHR 9 | ESP 7 | MON 13 | CAN 4 | USA 5 | FRA 15 | GBR 7 | EUR 8 | HUN 8 | TUR 6 | ITA 7 | BEL 8 | JPN 2 | CHN 9 | BRA Ret | 7th | 30 | |
| 2008 | Vodafone McLaren Mercedes | McLaren MP4-23 | Mercedes FO 108V 2.4 V8 | AUS 5 | MAL 3 | BHR 5 | ESP Ret | TUR 12 | MON 8 | CAN 9 | FRA 4 | GBR 5 | GER 5 | HUN 1 | EUR 4 | BEL 10 | ITA 2 | SIN 10 | JPN | CHN | BRA | 6th* | 51* |