A bonus is a set of several questions that the whole team can work together to answer. Bonuses are given as a reward to the team that answered a tossup immediately beforehand. A bonus is typically worth 30 points, and they have been standardized as three-part questions whose parts are worth 10 points each.
The team which answered the tossup is said to "control" the bonus, as they have the right to answer it. In formats with bouncebacks like PACE NSC, the other team has the opportunity to answer when the controlling team gets a question incorrect - the first team retains control of the bonus, though.
When a team answers a tossup correctly, they then receive a bonus consisting of a lead-in and three bonus parts.
The lead-in of the bonus is its introduction and comes before the first bonus part. Bonus lead-ins typically either identify the theme of the bonus, or give a brief clue (possibly an interesting or little-known fact) about the answer to the first bonus part. In modern quizbowl theory, these are recognized as the only two types of bonus lead-ins.
Each individual question in a bonus is called a part. The lead-in can be considered part of the first part, especially when it embeds a clue.
Three-part bonuses are intended to have an "easy part" accessible to most teams, a "middle part" (or "medium part") that about half the teams can answer, and a "hard part" that only the top teams at a given tournament should be able to answer. This is sometimes explicitly stated as 90%, 50%, and 10% of the field should be able to answer each.
- an answer will be relatively easier when used as the third part compared to when used as the first part because the theme will be clear and more context has been provided.
- the lead-in allows room for an additional clue to be added to the first part.
Writers can take advantage of these effects to tune the difficulty of their bonus.
Here is an outline of how bonuses play out:
- The moderator reads the lead-in and the first part of the bonus.
- The team that controls the bonus can confer and attempt to answer, or they may give a response of "no answer."
- Teams typically have five seconds to confer on each bonus part. The moderator will accept the first answer given by a member of the team that is directed to the moderator rather than a teammate. Teams are warned (prompted for an answer) when they have one second left to give an answer.
- They also have the option to skip the bonus, which is equivalent to saying "no answer" to all three parts simultaneously. This tactic is occasionally employed in timed formats, in which it may be advantageous to skip a bonus in order to hear the next tossup.
- The moderator rules on the answer given. If correct, they may verbally confirm with a phrase like "Correct" or "10 points" or they may simply proceed to the next part; if incorrect, they will typically reveal the answer.
- The moderator may optionally reveal acceptable answers or prompts listed in the answerline. The exception to this is when they are marked "accept/prompt, but do not reveal", which may be the case when the answer to a later part is part of an acceptable answer for a previous part.
- In formats with bouncebacks, the moderator will not reveal the answer and will instead "bounce" the bonus to the other team to allow them an opportunity to answer.
- The second and third parts function identically to the first part, sans the lead-in.
- The moderator verbally confirms the total score on the bonus to remind the teams and the scorekeeper.
- The bonus is over and the next tossup is read.
7. A daughter of Phorcys and Ceto, this figure was killed by a man on a quest to obtain her head as a wedding gift to Polydectes. For 10 points each:
 Name this monster, a Gorgon who had snakes for hair, who was slain by Perseus.
 This creature was born, along with Chrysaor, when Perseus beheaded Medusa.
 Name either of Medusa’s two sisters, Gorgons who, unlike her, were immortal.
ANSWER: Stheno [or Euryale]
(from 2012 ACF Fall)
Each part leads with the point value in square braces (""). They are then followed by their answerline.
The lead-in of this bonus is the section before the first "", which contains the phrase "for 10 points each." In this case, an additional clue for the first part is included.
Defunct styles of bonuses
Before bonuses with an easy-middle-hard at 10 points a pieces became completely standardized, bonus formats could vary from bonus to bonus within a tournament. Examples of such various formats included:
- four answer, 5 for one, 10 for two, 20 for three and 30 for getting all four answers correct
- two answers, each with two clues, with teams given 15 after the first clue for each answer or 5 after the second ("15-5")
- five answers, five points per answer with an additional five for all correct
- six answers, five points each (this and the above are used mainly for list bonuses)
- two difficult answers of 15 points each
- one answer, three clues of decreasing difficulty, with teams given 30 points after the first clue, 20 after the second, 10 after the third ("30-20-10")
- three answers of increasing difficulty, with teams given 5 points for the first, 10 for the second, 15 for the third ("5-10-15")
- three answers, each with two clues of variant difficulty, with teams given 10 points for the harder clue or 5 for the easier ("10-5")
- some local high school formats used one-part bonuses or bonuses that were worth 20 points
All of these forms are now strongly discouraged, if not forbidden outright, in standard high school and collegiate play for reasons of fairness.
Some local formats have the moderator read the entire bonus, then allow the team to confer on all parts for thirty seconds, and then give their answers.