| Type | Power | Accuracy | PP |
| Fight | 20 | ||
| Target | Contact | TM/HM | |
| User only | No | TM 08 | |
Both the Attack and Defense stats of the pokemon using Bulk Up will increase by 1 step on the Stat growth scale.
Because of the uniformity of the increases of the value, this increase translates into an increase equivalent to half of the original value of the Attack and Defense stats each time this move is used. In more definite terms, starting with no modifiers, the 1st use of the move will make the Attack and Defense stats 150% of the original value, the 2nd will make it 200% of the original value, the 3rd will make it 250% of the original value, etc.
Bulk Up will always fail if it has already been used 6 times by the same pokemon, without a move that lowers Attack and/or Defense being used on or against the pokemon using Bulk Up. This is due to the fact that a stat may only be raised by a maximum of 6 steps, until it is reset by the use of Haze or the pokemon is switched out normally. The maximum is the limit of how many increases can be applied to a stat. If another move increases the Attack and/or Defense stats of the pokemon using Bulk Up, the number of steps that it increases the Attack and/or Defense stats by will count toward the 6 step limit, and reduce the number of times that Bulk Up can be used appropriately. If a move changes the step levels of either Attack or Defense seperately (for instance, an opposing pokemon using Growl), then Bulk Up will not fail until both Attack and Defense have hit the 6 step-level limit. However, this will not cause the stat that had the greater number of steps to increase beyond the 6 step-level limit, it will simply continue to raise the lower of the two stats until it hits that limit.