Hidden Machines (HMs) in Black/White/Black 2/White 2
Pokémon Black & Pokémon White actually cut back the number of HMs from previous games, from eight in Generation 4 down to six. Black 2 & White 2 keep the same list.
In Black & White, none of the HMs are required to complete the main storyline except Cut, which is used on a single tree. However, they are useful in most areas to access extras like items behind trees or across water. Several large rocks can be moved with Strength to create shortcuts. Flash remains a TM but is useful in certain caves. Headbutt and Rock Smash have no use outside of battle in the Unova region. Dive is only used for one area - the Abyssal Ruins underneath Undella Bay (more details & map).
Below we list every Pokémon available in Generation 5 with the HMs they can learn in Black & White and their sequels. The Pokémon can be filtered by ticking the checkboxes - this is useful for deciding on an
HM Slave - a Pokémon knowing only HM moves (in order to save all four spots for good moves on other Pokémon).
Where to find the HMs in Black/White and Black/White 2.
B/W: Striaton City - from Mokomo.
B2/W2: Virbank City - from Roxie.
B/W: Driftveil City - from Bianca.
B2/W2: Route 5 - from Bianca.
B/W: Twist Mountain - from Alder.
B2/W2: Route 6 - from Cheren.
B/W: Nimbasa City - west.
B2/W2: Castelia Sewers - from Hugh.
B/W: Route 18 - southwest corner.
B2/W2: Victory Road - from N.
B/W: Undella Town - from girl outside PokéCenter.
B2/W2: Undella Town - from Hugh after defeating Elite Four.
Pokémon HM chart