FREE DELIVERY on orders over £15

Soap vs. Shampoo Bar vs. Liquid Shampoo

Which one is best for both you and the planet?8 min read5 March 2023 (Updated: 6 March 2023)

As con­sumers be­come more en­vi­ron­men­tal­ly-con­scious, they're seek­ing out al­ter­na­tives to plas­tic-pack­aged prod­ucts for their per­son­al care. As a re­sult, a big shift is hap­pen­ing in hair­care. Peo­ple are re­con­sid­er­ing tra­di­tion­al liq­uid sham­poos and the pol­lut­ing big plas­tic bot­tles they're sold in. They are ex­plor­ing pos­si­bly more eco-friend­ly op­tions like soap and sham­poo bars. But which method is ac­tu­al­ly best for your hair? Let's ex­plore the sim­i­lar­i­ties and dif­fer­ences be­tween soap, sham­poo bars, and liq­uid sham­poos.

Form Fac­tor

The main dif­fer­ence be­tween soap, sham­poo bars, and liq­uid sham­poos is the form in which they come. Al­though soap can re­fer to dif­fer­ent prod­ucts, peo­ple most of­ten use "soap" to mean a sol­id block of long-last­ing soap that, in the­o­ry, could be used for both body and hair. A big change hap­pened in the 1930s when Hans Schwarzkopf came up with the idea of mix­ing sham­poo pow­der with wa­ter. He wasn't the only one, as John Breck cre­at­ed a sim­i­lar prod­uct in the form of liq­uid sham­poo in North Amer­i­ca around the same time. The fu­ture for sham­poo was set for the next decades to come: a big bot­tle where sham­poo­ing and con­di­tion­ing agents could be di­lut­ed in wa­ter for con­ve­nience and big­ger prof­its.

But then, it came the cli­mate cri­sis and peo­ple start­ed to won­der if liq­uid sham­poos and big bot­tle of plas­tic was the best op­tion for one's hair. The an­swer came in the form of sham­poo bars, with a sim­i­lar form fac­tor to soap and all the ben­e­fits of sa­lon-grade liq­uid sham­poos.

In­gre­di­ents, form fac­tor, and method of use dif­fer in all three cas­es, but choos­ing the right op­tion shouldn't be just down to con­ve­nience. Each prod­uct has its pros and cons when it comes to con­sid­er­ing hair types and en­vi­ron­men­tal im­pact.


Us­ing soap to wash your hair may seem like a sim­ple, in­ex­pen­sive op­tion. Not only that, a bar of soap can last a long time and is very en­vi­ron­men­tal­ly friend­ly when it sold in plas­tic-free pack­ag­ing. How­ev­er, there's more to soap than meets the eye.

Soap is a cleans­ing agent made from a com­bi­na­tion of fats and an al­ka­li, such as sodi­um hy­drox­ide. What we hold in our hands is the re­sult of a saponi­fi­ca­tion process and chem­i­cal re­ac­tions that re­sults in an al­ka­line prod­uct and pH lev­el of more than 7. Most, if not all, soaps are not pH bal­anced and as a re­sult may be very harsh to use for hair and beards. In­deed, many der­ma­tol­o­gists would not rec­om­mend­ soap for use on the hair and scalp be­cause it can strip hair of its nat­ur­al oils and cause dry­ness and ir­ri­ta­tion.

Tra­di­tion­al Liq­uid Sham­poo: Its Ad­van­tages and Dis­ad­van­tages

If soap is not that good for your hair, beard and scalp, then no won­der why tra­di­tion­al sham­poos be­came the go-to op­tion at the show­er. Liq­uid sham­poos are the most com­mon type of sham­poo due to their con­ve­nience and va­ri­ety of of­fer­ing at su­per­mar­kets, phar­ma­cies, and drug stores. They come in a wide range of for­mu­la­tions de­signed for dif­fer­ent hair types and con­cerns, mak­ing it easy to find one that fits your spe­cif­ic needs. They’re made with var­i­ous in­gre­di­ents to clean the hair and scalp, in­clud­ing sur­fac­tants, oils, and fra­grances.

Also, tra­di­tion­al liq­uid sham­poos are more ef­fec­tive at lath­er­ing and re­mov­ing dirt and oils than soaps. They of­ten con­tain chem­i­cals like sul­phates that gen­er­ate that rich foam we all love, as well as a lux­u­ri­ous and sat­is­fy­ing show­er ex­pe­ri­ence. The prob­lem comes when one starts read­ing the small print and re­alis­es the chem­i­cals like sul­phates and parabens are de­rived from pe­tro­le­um and fos­sil fu­els. Not only, the ex­trac­tion of raw ma­te­ri­als in the form of fos­sil-fu­els is dam­ag­ing the en­vi­ron­ment, nu­mer­ous con­sumers have for long raised con­cerns about ad­verse re­ac­tion in their skin and hair.

In short, liq­uid sham­poos may con­tain syn­thet­ic in­gre­di­ents, fra­grances, and harsh chem­i­cals that can dry or ir­ri­tate hair and scalp. If you can't tell what's in­side the bot­tle, some­one is prob­a­bly hid­ing where the in­gre­di­ents came from too.

Sham­poo Bars

Sham­poo bars are sol­id items de­signed to be used in place of liq­uid sham­poos on wet hair. They are used dif­fer­ent­ly, but sham­poo bars have be­come in­creas­ing­ly pop­u­lar in re­cent years due to their many ben­e­fits. Just to name a few, sham­poo bars:

  • Are more sus­tain­able due to re­duced pack­ag­ing, and po­ten­tial­ly be­ing plas­tic-free. They are of­ten pack­aged in re­cy­clable ma­te­ri­als, and pro­duce less waste than liq­uid sham­poos.
  • Are much more con­ve­nient for tak­ing them away. A sham­poo bars fits per­fect­ly with­in a gym bag. And as a sol­id sham­poo for­mat, you can take them to an air­port with­out hav­ing to show them at the se­cu­ri­ty gate.
  • Typ­i­cal­ly con­tain few­er chem­i­cals and ad­di­tives, which can be ben­e­fi­cial for those with sen­si­tive scalps or al­ler­gies. If the bar is nat­ur­al and ve­g­an, then in­gre­di­ents will also be more en­vi­ron­men­tal­ly friend­ly.
  • Can be a cost-ef­fec­tive op­tion as they last longer than tra­di­tion­al sham­poo bot­tles.

Be­cause of their sol­id for­mat, in­gre­di­ents tend to dif­fer from their liq­uid coun­ter­parts. Many sham­poo bars con­sist of es­sen­tial oils, kinds of but­ter, sur­fac­tants, and oth­er nat­ur­al in­gre­di­ents. The shift to nat­ur­al al­ter­na­tives doesn't mean they're a less ef­fec­tive op­tion, as the sol­id sham­poo mar­ket has evolved and ma­tured a lot in the past few years. Sham­poo bars now come in a va­ri­ety of for­mu­la­tions de­signed for dif­fer­ent hair types, mak­ing it eas­i­er to find one that fits your spe­cif­ic needs.

Hav­ing said all that, at Dis­rup­tor Lon­don, we have made ex­ten­sive cus­tomer re­search on why the adop­tion of sham­poo bars is slow­er than one might ex­pect from the amaz­ing ben­e­fits above. One of the rea­sons is that they may not be as ef­fec­tive at lath­er­ing. This hap­pens be­cause tra­di­tion­al liq­uid sham­poos would typ­i­cal­ly con­tain petro­chem­i­cals like sul­fates to cre­ate the rich foam con­sumers ex­pect. By shift­ing to nat­ur­al al­ter­na­tives, we all had to start from scratch in terms of for­mu­lat­ing the per­fect sham­poo.

Cus­tomers have also told us that the sham­poo bars they have tried in the past may be more dry­ing to the hair and scalp than liq­uid sham­poos. The lat­ter may in­clude some sil­i­cones and oth­er chem­i­cals that add that sen­sa­tion of soft­ness af­ter each wash. An old trick is to use ap­ple cider vine­gar af­ter each use if you're deal­ing with a dry, itchy scalp, but some con­sumers feel like this is very in­con­ve­nient.

Here at Dis­rup­tor Lon­don, we have spent more than two years in get­ting all those con­cerns right. The ben­e­fits that sham­poo bars of­fer over liq­uid sham­poos, let alone al­ka­line soaps, are too big to give them a miss. Sham­poo bars are the fu­ture of plan­et-pos­i­tive hair­care, and we want them to work.

We have for­mu­lat­ed bars like Bal­ance, which helps to main­tain a healthy mi­cro­bio­me, as well as Flake Free, for itchy and dry scalp, that lath­er eas­i­ly. We have cre­at­ed a unique for­mu­la with a dual-charge sur­fac­tant sys­tem that cre­ates a very rich, silky foam. All of our bars also con­tain very rich con­di­tion­ing in­gre­di­ents like pan­thenol and ker­atin. And all that, with­out com­pro­mis­ing on the en­vi­ron­men­tal as­pect and all the ben­e­fits we have learned to love about sham­poo bars.

How to Choose the Right Prod­uct?

We wouldn't rec­om­mend us­ing soap for your hair, giv­en their al­ka­line and dry­ing prop­er­ties. Liq­uid sham­poos and con­di­tion­ers are wide­ly avail­able, but they are also very pol­lut­ing and un­sus­tain­able for the plan­et.

Re­gard­less of which op­tion you end up go­ing for, first and fore­most, please con­sid­er your hair type and any spe­cif­ic con­cerns you may have. For ex­am­ple, if you have dam­aged hair or sen­si­tive skin, a gen­tle sham­poo bar like Calm may be the best op­tion as it will be kinder on your strands than a harsh liq­uid sham­poo. Like­wise, if you suf­fer from a con­gest­ed scalp, then some­thing like Detox would be ex­cel­lent for you, as it com­bines two types of ex­fo­li­at­ing mech­a­nisms with the cleans­ing prop­er­ties of up­cy­cled char­coal.

If you want to re­duce your en­vi­ron­men­tal im­pact, then opt­ing for sham­poo bars pack­aged in eco-friend­ly ma­te­ri­als may be more up your al­ley. If you find prod­ucts sold in a box, then look out for the FSC sym­bol to make sure the pa­per comes from sus­tain­able sources.

Not all sham­poo bars are cre­at­ed equal. While some man­u­fac­tur­ers are dis­guis­ing old soaps as in­no­v­a­tive sham­poo bars, oth­ers are us­ing for­mu­las that are not that con­ve­nient and ef­fi­cient. Take the time to re­search the dif­fer­ent op­tions avail­able and ex­per­i­ment with what works best for you per­son­al­ly. It may take some tri­al and er­ror, but find­ing the right prod­uct for your hair can make all the dif­fer­ence in achiev­ing healthy-look­ing locks.

Above all, you should al­ways choose prod­ucts made with your hair type and needs in mind. Also, pay at­ten­tion to the in­gre­di­ents list when shop­ping for hair­care prod­ucts. That way, you will know you’re us­ing good and ef­fec­tive prod­ucts.

As a rule of thumb, when shop­ping for a sham­poo bar, look out for:

  • Are they soap free?
  • Do they con­tain any petro­chem­i­cals like sul­fates or parabens?
  • Do they lath­er well and cre­ate a rich foam?
  • Do they con­tain con­di­tion­ing agents that are go­ing to take care of your hair, scalp, and skin?

If you find that a par­tic­u­lar brand doesn't an­swer all those ques­tions, then one may con­sid­er whether ac­count­abil­i­ty and trans­paren­cy is one of their val­ues. Ul­ti­mate­ly, con­sumers shouldn't have to bend over back­wards to de­cide what's best for them and the plan­et.