Hair Mask vs Conditioner: What's the Difference and Do You Need Both?

Hair Mask vs Conditioner: What's the Difference and Do You Need Both?

    Both sit in the shower. Both go on after shampoo. Both promise softer, smoother hair. So what's actually different about a hair mask and a conditioner — and do you need to be using both?

    The short answer is yes, but for different reasons. Here's the longer one.

    What a Conditioner Actually Does

    Conditioner is a daily maintenance product. Its job is to smooth the hair cuticle after shampooing, restore some of the moisture stripped during cleansing, reduce static and frizz, and make hair easier to detangle and style.

    A good conditioner works on the outer layer of the hair shaft — the cuticle — sealing it down so hair feels soft, looks shiny, and behaves. It's designed to be rinsed off relatively quickly (most conditioners are optimised for 1–3 minutes of contact time), and it's meant to be used every wash.

    What conditioner isn't designed to do is repair structural damage. It maintains. It doesn't rebuild.

    What a Hair Mask Does Differently

    A hair mask — also called a hair treatment or deep conditioner — is a concentrated repair product. Where conditioner works on the surface of the hair, a mask is formulated to penetrate deeper into the cortex of the hair shaft, addressing damage at a structural level.

    Think of it this way: conditioner is your daily moisturiser, and a hair mask is your serum. Different job, different depth, different frequency.

    Masks typically need more contact time — 5 to 20 minutes — to do their work, and they're used once a week or fortnightly depending on how much damage you're dealing with.

    Signs Your Hair Needs More Than a Conditioner

    If your hair is doing any of the following, your conditioner alone isn't cutting it and a mask should be in your rotation:

    • Snapping or breaking when you brush or style it
    • Feeling rough or coarse even after conditioning
    • Looking dull regardless of product
    • Taking a long time to dry but still feeling dry once it does
    • Recovering slowly (or not at all) from colour, heat, or chemical treatments

    These are signs of structural damage — compromised bonds within the hair shaft — that surface-level conditioning can't fix.

    How to Use Both in Your Routine

    The combination is simpler than it sounds.

    On regular wash days: Shampoo, then conditioner. Apply conditioner from mid-length to ends, leave for 1–3 minutes, rinse.

    On treatment days (once a week or fortnightly): Shampoo, then use your hair mask instead of your conditioner. Apply from mid-length to ends — or all over if your scalp needs treatment too — and leave for the recommended time before rinsing thoroughly.

    You don't need to use both on the same wash. The mask replaces the conditioner on treatment days, not supplements it.

    Which Products to Use

    For everyday conditioning

    The right conditioner depends on what your hair needs most. St. Louis Says has four options:

    All four are sulphate-free, paraben-free, and vegan.

    For weekly repair

    The Resurrection Repair Hair Treatment Mask is a concentrated treatment designed for damaged, weak, or breakage-prone hair. It works across hair types and pairs with any of the conditioner options above — use whichever conditioner suits your hair on regular wash days, and swap in the Resurrection Repair mask once a week.

    Apply it after shampooing, work it through from mid-length to ends, leave for 5–10 minutes (or longer for more intensive repair), then rinse thoroughly.

    The Simple Version

    Conditioner: every wash, fast, maintenance. Hair mask: once a week, slow, repair.

    You need both because they're doing different things. One keeps your hair in good shape day to day. The other fixes damage that daily conditioning can't reach.

    If you've only ever used conditioner and your hair is still feeling dry, breaking, or dull — the mask is where to start.

    Browse the full St. Louis Says range or shop by hair concern.