High-risk format

Some versions of Who Wants to Be a Millionaire? have adopted a high-risk format, which disables the second fixed milestone in favor of an adjustable milestone that the contestant can set anywhere between question 6 and question 14, but still retains the first fixed milestone at question 5. The UK version adopted the high-risk format for its 20th Anniversary celebration in 2018.

Mechanics
Before the mechanics of the high-risk format can be explained, the Money Tree must be shown first, in order to put it into perspective. The money tree shown below is the original UK version, which was used for the 2018 revival, which adopted the high-risk format. Guaranteed milestones at shown in bold.


 * £100
 * £200
 * £300
 * £500
 * £1,000
 * £2,000
 * £4,000
 * £8,000
 * £16,000
 * £32,000
 * £64,000
 * £125,000
 * £250,000
 * £500,000
 * £1,000,000

Normally, question 10, worth £32,000, would be a fixed milestone, as it was originally in the old format, but in the new high-risk format, the contestant can now adjust the second milestone anywhere they want, from as low as question 6, worth £2,000, up to as high as question 14, worth £500,000.

Advantages and disadvantages
If the contestant sets the second milestone too high or too low, flunking out may be much more costlier than normal. On one hand, if the contestant sets the second milestone too low, at only £2,000, and flunks on the £1,000,000 question, they lose £498,000, which is £30,000 more than the £468,000 they would normally lose if the second milestone was set at its traditional level of £32,000. On the other hand, if the contestant sets the second milestone too high, at £500,000, and flunks on the £1,000,000 question, they won't lose anything, but if they flunk out on the £500,000 question itself (or any question prior), they will drop all the way back down to just £1,000; if they flunk on the £500,000 question, they will lose £249,000, which is £31,000 more than what they would normally lose if the second milestone was set at its traditional level of £32,000.

Extra-high-risk formats
If both fixed milestones are disabled, the format is called an extra-high-risk format, which allows the player to select only one adjustable milestone, and if they flunk out before they reach that milestone, they will lose absolutely everything and leave with nothing at all. This is the format used by the Russian version of the show, and many Russian contestants, including a number of celebrity contestants, have ended up leaving empty-handed due to flunking out prior to reaching their selected milestone.

See for contestants who left with nothing due to playing on an extra-high-risk format.