The UK Championship was the main tournament of the UK series of Robot Wars. There were seven series of UK Championship in Robot Wars, before the show was cancelled in 2004, with the UK Champion determined in Roaming Robots tournaments ever since. All seven main series of Robot Wars used different formats, with the number and structure of heats and number of robots in each heat varying every year.
The UK Championships did not cease with the end of televised competition however, and are still continuing today, overseen by the Fighting Robot Association.
- Main article: Robot Wars: The First Wars
In the first series, there were six heats. All six heats had six competing robots. The first round of each heat was The Gauntlet, an obstacle course which every robot had to try and complete, with the worst performing robot being eliminated. The second round was The Trial, a small event, such as British Bulldog or Sumo. The five remaining robots would compete, and again the poorest performing robot would be eliminated. The third round was The Arena. The four remaining robots were separated into two one-on-one battles, with the winners going through to the Heat Final. The Heat Final was another one-on-one battle, with the winner going through to the Grand Final. The Grand Final was not a separate episode, but one battle at the end of the sixth heat. All the robots fought at once, with no breaks (Unlike an Annihilator), with the longest surviving robot being declared champion.
- Main article: Robot Wars: The Second Wars
The format of the series changed dramatically in Series 2. The amount of heats doubled, and there were now two semi finals, and the grand final was a separate episode. However, the format of each heat stayed the same, and the semi finals followed a similar format, with the Gauntlet as the first round of the semi final, followed by a Trial stage, before the Arena stage. The two robots who won their fights went through to the Grand Final. The Grand Final consisted of two one-on-one eliminators, before the final battle to decide the champion. The losers of each eliminator would fight each other for 3rd place before the final battle. This format that was used for the Grand Final was continued for every series that followed.
- Main article: Robot Wars: The Third Wars
Series 3 featured a complete change to the format. Most notably, the Gauntlet and Trial stages were scrapped, in favour of it being entirely fight based. The amount of heats increased to 16, with there now being eight robots in each heat. There were four one-on-one Round 1 battles, before having two semi finals, and a heat final. There were still two semi finals, but there now only two rounds in the semi finals. There were four round 1 battles, with the winners going to round 2 of the semi finals, and the two winners going through to the Grand Final.
- Main article: Robot Wars: The Fourth Wars
The format largely remained the same in Series 4. However, there were now only six robots in each heat. The first round was now two three way melees, with only one robot eliminated in each melee, leaving four robots. The rest of the series followed the same format as Series 3. This was the last series to feature 6 robots per heat.
- Main article: Robot Wars: The Fifth Wars
Series 5 featured only featured twelve heats, but the amount of robots increased back to eight. The Heats followed the same format as Series 3, however, the semi finals featured a new format. There were six robots in each Semi final, with three initial battles. For the first time, the three losers went into a three way "Loser's Melee", with only one robot surving to get back into the competition. There were then two more one-on-one battles, with the two winners going through to the Grand Final.
- Main article: Robot Wars: The Sixth Wars
The format was almost entirely unchanged in Series 6 from Series 5. The only changes were that Round One now consisted of two four way melees, with two robots being eliminated in each one. The amount of heats, robots in each show and format of the semi finals stayed the same from Series 5.
- Main article: Robot Wars: The Seventh Wars
As Five took over the show, the format was changed for one last time. Whilst the format of the heats stayed the same as Series 6, there were now 16 heats for the first time since Series 4. The semi-finals consequently followed the Series 3-4 format. For the first time, since Robot Wars had moved to a commercial channel, Craig Charles recorded links for the show before and after the advert breaks.