- For Bonus Stages in general, see here.
Bonus Stages in Sonic the Hedgehog Spinball are special areas that the player can visit separate from the main game. There are a total of four Bonus Stages to complete.
The player can play the Bonus Stages after passing through the regular levels. There is also a fourth Bonus Stage that becomes playable if the player collects all the Rings in a level; once that task is completed, a Bonus Gate into this Bonus Stage will appear in the level.
The Bonus Stage takes place inside a regular pinball cabinet, with Sonic at the controls. When playing in the Bonus Stages, Sonic himself can be seen playing the pinball table in the reflection of the windows in the background.
The Bonus Stages and their gameplay are set up like real-life pinball machines. Each Bonus Stage has its own tasks to complete for gathering more points to the player's total score. The player will not lose anything should they fail, but by completing them, they each will reward the player with the "Rising Jackpot" bonus which adds 10,000,000 points to the final jackpot once the player finishes the game.
The player can only control the Flippers and are given three balls to play with. Flipper controls are the same as in the normal game, but the ball cannot be controlled with . Also, pressing , and at the same time will make Sonic shake the machine, although repeated shakes can cause a tilt and disable the Flippers, rendering them unresponsive to the player's commands.
Completing the bonus stages are optional and serves only to increase the player's score. The three bonus rounds, in corresponding order to the normal zones, are:
This Bonus Stage can be played after completing Toxic Caves. The player's objective here is to free animals from the purple capsules behind Dr. Robotnik, who is riding in his Egg Mobile. If the player tries to hit Robotnik before blowing up the purple capsules, he will bounce the ball back. When the animals are freed, the player is able to hit Robotnik.
This Bonus Stage can be played after completing Lava Powerhouse. The player's objective here is to knock out all teeth on the figure that looks like Robotnik's face.
This Bonus Stage can be played after completing The Machine. The player's objective here is to destroy the giant Capsule and free the animals within. During gameplay, several Scratches will be encircling the Capsule, forming a protective barrier. However, these robots can be destroyed with the pinball.
This hidden Bonus Stage can be entered from any level through the Bonus Gates that are hidden around the boards. To summon the gates, the player must collect every Ring in the respective level. The player's objective here is to destroy the Crawl, who is protected by a pair of Cluckers, using pinballs.