How to Use a Shampoo Bar

1. Wet hair thoroughly. Chagrin Valley asks for a lot of water, saturating hair to the roots.
2. Wet the bar. Kitsch and Ethique both tell you to wet hair and bar.
3. Lather. Rub the bar between your hands, or glide it over the top of your head; see the next section.
4. Massage the scalp. Work the lather in with your fingertips (Kitsch, Ethique).
5. Rinse thoroughly. Ethique says rinse completely; Chagrin Valley says rinsing should take longer than lathering.
6. Repeat if wanted. Kitsch: rinse and repeat as needed. Bottle None: shampoo twice.
7. Follow with conditioner if you use one. Ethique's instructions say to follow with its conditioner.
8. Let the bar dry before the next use; see how to store a shampoo bar.

Brands differ.

Brand	Method as published
Kitsch (Castor Oil, Rice Water)	Rub bar between hands into a rich lather or paint it directly onto the scalp
Kitsch (Tea Tree & Mint)	Wet hair and bar; massage the bar into scalp and strands to lather
Ethique	Massage the bar directly onto the scalp and work into a lather with hands
Bottle None	Lather in hands or directly on hair
Chagrin Valley	Build lather between hands and use only the lather on the scalp (best for thick, curly, coarse or new users); or rub on top of the head only, in one direction, for thinner hair. Do not lather the lengths with the bar

The choice is mostly about length and thickness. Chagrin Valley's reasoning is that lathering the lengths with the bar coats strands with soap oils; its method relies on rinsing lather down the lengths with fingers. For long or thick hair, hands-first is the safer starting point.

Only Kitsch quantifies it: its rice bar page says up to 100 washes at approx. 0.032 oz per wash, about 0.9 g. Ethique's 80+ washes from a 110 g bar implies roughly 1.4 g per wash, by division. Read both as averages: longer and thicker hair uses more. Using less bar and more lather from water is also what extends bar life; see how long a shampoo bar lasts.

Longer than with liquid shampoo, according to the one brand that gives a rule. Chagrin Valley says rinsing 'should take longer than washing and lathering time', lifting sections of long or thick hair and not skipping the nape or back of the head. It adds that if residue shows before or after washing, an apple cider vinegar rinse or a baking soda clarifying rinse is its suggested fix. If hair stays filmy, see the transition period.

Brands differ. Kitsch, Ethique, HiBAR and Bottle None sell matching conditioner bars and pair them in their instructions. Chagrin Valley and J.R. Liggett's say most people do not need a conditioner with their soap-based bars, because they are made with oils and butters and no detergents. Both are brand claims; hair length and texture will decide.

Three recur in the pages reviewed: not wetting hair enough before lathering, not rinsing long enough, and leaving the bar sitting wet. Bottle None adds that a toning purple bar is a specialty bar, used 1 to 2 times a week at most for strong blonde toning. For toning bars see best purple shampoo bars.

Specialty bars carry their own limits. Bottle None says to leave its purple bar on for 1 to 5 minutes during the second wash and to use it 1 to 2 times a week at most; Ethique suggests 1 to 2 times a week for its Clarifying bar; Ethique's Purple bar is formulated for daily use. See best purple shampoo bars and best clarifying shampoo bars.