- 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 four Bonus Stages in the Sega Mega Drive version of the game, and three in the Sega Game Gear version.
The player can play the Bonus Stages after passing through the regular levels. There is also a fourth Bonus Stage in the Mega Drive version of the game 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.
In the Mega Drive version of Sonic the Hedgehog Spinball, 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.
In the Game Gear version of the game, the Bonus Stage takes place in the Egyptian-themed level.
In the Mega Drive version of Sonic the Hedgehog Spinball, the Bonus Stages and their gameplay are set up like real-life pinball machines. Each Bonus Stage has its own requirements 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. Also, pressing , and at the same time will shake the machine, although doing so can disable the Flippers, rendering them unresponsive to the player's commands.
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 Gate that are hidden around the boards. To summon the gate, 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.
In the Game Gear version of Sonic the Hedgehog Spinball, the Bonus Stage is set up like a real-life pinball machine where the player can score extra points and Continue. When beginning a Bonus Stage, Sonic is dropped into a cage with Rings, bumpers, treasure boxes, and enemy robots. The player's objective here is to collect as much loot as possible within the time limit. The player can as well only control the Flippers.
A treasure box here can be opened with three hits, which will reward the player with either 1,000 points, ten Rings, a 1-Up, a Continue, or extra time. Collecting at least half of the Rings in Sonic's cage will unlock an adjoining cage. Each round consists of three cages, but if the player fails to reach the exit within the time limit, they will loose all their loot.