This lifeline allowed the contestant to make two guesses on a question, but required them to play out the question, forbidding them to walk away or use any further lifelines. The lifeline did not get reinstated if the first guess turned to be correct.
On Super Millionaire, this lifeline (alongside Three Wise Men) was only given to contestants who had correctly answered the tenth question, the second milestone level. As the penalty for an incorrect answer to a top-tier question was usually hundreds of thousands, if not millions of dollars (e.g., answering the 13th question incorrectly made a contestant lose $900,000), and that contestants who chose to use Double Dip were forced to answer the question no matter what, the host Regis Philbin used to ask contestants who intended to use Double Dip for confirmation that they really want to use the lifeline before actually letting them have their two guesses.
On the clock format of the U.S. show, this lifeline was available to contestants as soon as they began their game (they no longer needed to earn it). Once a contestant stated that they wanted to use this lifeline, the clock would immediately stop to let contestants make their first guess. If it turned to be incorrect, the host would give a brief explanation and the clock would resume. Contestants who failed to make their second guess before the clock expired were penalized as if they answered incorrectly and went down to the last guaranteed sum (normally, they would be forced to walk with what they won up to where they are).
- Starting 4 September 2010, the Double Dip has appeared on the risk format on the Russian version of the show: Kto khochet stat' millionerom?.
- On one occasion, a contestant used his Double Dip during the clock format of the U.S. show on this $25,000 question: "How many U.S. states have names that begin with the word 'New'? A: 2, B: 3, C: 4, D: 5" (the correct answer was 4). His first guess was 3, which was incorrect. As the clock expired, he attempted to walk away before the host Meredith Vieira explained that he was not allowed to walk with Double Dip. He ended up winning $1,000.
- In versions of the game that feature both Double Dip and 50:50, it is possible for a contestant to use their 50:50 to eliminate two of the wrong answers, and then use their Double Dip to determine the correct answer. Although noticed by some Super Millionaire contestants, no one managed to keep their 50:50 lifeline past the $100,000 milestone question. But in the Russian, Turkish, and Austrian Format, a few of them use both 50:50 and Double Dip.