Sodium Hyaluronate vs. Hyaluronic Acid: What’s the Difference?

If you have ever flipped a skincare product over and squinted at the ingredients list, you are not alone in spotting both “sodium hyaluronate” and “hyaluronic acid” and wondering whether they are the same thing, different things, or whether one is somehow better than the other. It is one of the most common points of confusion in skincare - and it is completely understandable. The labels are technical. The naming conventions are inconsistent across brands. And most products offer no explanation whatsoever.

This guide fixes that. Here, you will find a clear, no-BS breakdown of the sodium hyaluronate vs. hyaluronic acid question: what each ingredient is, how they differ at a molecular level, how they work differently in the skin, why the best formulas use both, how to decode your INCI list like a pro, and which INKEY products contain all the forms worth knowing about.

A quick note on the name INKEY: it comes directly from the INCI list - the International Nomenclature of Cosmetic Ingredients, the standardised global system used to name every ingredient on every skincare label. It is a fitting name for a brand built entirely on ingredient transparency and education. No smoke. No mirrors. Just the science, explained clearly.

Shop the hero products featured in this guide:

Hyaluronic Acid Serum - from £9 / 30ml. Contains both sodium hyaluronate and hyaluronic acid in a 2% multi-molecular complex.
Ectoin Hydro-Barrier Serum - £15 / 30ml. Contains all four forms of hyaluronic acid in a single formula.

What Is Hyaluronic Acid and Why Does Your Skin Need It?

Before the comparison between sodium hyaluronate vs. hyaluronic acid can land with full clarity, it is worth establishing exactly what hyaluronic acid is and why it matters so much in skincare. Skipping this step is where most confusion begins.

Hyaluronic acid - commonly abbreviated to HA - is a naturally occurring polysaccharide found throughout the human body. It is present in the skin, in the fluid that cushions joints, and in the connective tissues that hold everything together. The body produces it endogenously, meaning it manufactures its own supply. And it is remarkably good at one specific job: attracting and holding onto water. Hyaluronic acid can bind up to 1,000 times its own weight in water, which makes it one of the most effective moisture-retaining molecules found in nature.

In skincare, hyaluronic acid functions as a humectant. A humectant is an ingredient that draws water molecules towards itself - either pulling moisture from the environment or from the deeper layers of the skin - and holds it in place. This is what gives well-formulated HA products their immediate, visible effect: skin that feels more plump, looks more hydrated, and has a smoother, more supple texture within minutes of application.

Here is something that trips people up: hyaluronic acid is not an exfoliating acid. Despite the word “acid” in the name, it has nothing in common with glycolic acid, salicylic acid, or lactic acid. The “acid” in hyaluronic acid simply describes its molecular structure as a type of sugar acid - a polysaccharide chain. It does not exfoliate, it does not cause sensitivity, and it does not interact negatively with other actives. In fact, it is one of the most universally compatible skincare ingredients in existence.

Hyaluronic acid works for every skin type. Dry skin needs it for obvious reasons. Oily skin benefits from it because a well-hydrated skin barrier is less likely to overproduce sebum in compensation for dehydration. Combination skin, sensitive skin, and mature skin all respond well to it. It is non-comedogenic, meaning it does not clog pores. It is non-irritating. And crucially, it does not displace or interfere with other actives - it can be used comfortably alongside retinol, vitamin C, niacinamide, and exfoliating acids.

As the body ages, its natural production of hyaluronic acid declines significantly. This is one of the key reasons that skin loses its characteristic plumpness and bounce with age - the internal reservoir that once kept skin cushioned starts to dry up. Topical HA does not replace the body’s own production in any permanent way, but it does supplement it by delivering hydration at the skin’s surface and within the upper layers of the epidermis.

Quick Facts: Hyaluronic Acid

What it does: Humectant - attracts and holds water in the skin
Who it’s for: All skin types, including sensitive and blemish-prone skin
When to use: AM and PM, applied to slightly damp skin before moisturiser
Key property: Holds up to 1,000x its weight in water

One important distinction that often gets conflated: hydrating and moisturising are not the same thing. Hyaluronic acid hydrates - it draws water into the skin. A moisturiser locks that water in by forming a protective seal over the surface, preventing transepidermal water loss. Both steps are needed for the full benefit. Applying HA and skipping your moisturiser is like filling a leaking bucket. For a deeper look at this distinction, read The Difference Between Moisturising and Hydrating.

The practical tip that makes the most difference: always apply HA-family products to slightly damp skin. Immediately after cleansing, before the skin has fully dried, is ideal. This gives the humectant direct access to ambient moisture to draw from, amplifying its effectiveness. On completely dry skin in a very low-humidity environment, a humectant may actually draw moisture from the deeper layers of the skin instead - which is why sealing it in with a moisturiser is always the essential follow-up step.

For a full deep-dive on what hyaluronic acid is and all its skin benefits, visit our complete Hyaluronic Acid ingredient guide. And if you are unsure whether you actually need it in your routine right now, this blog on 5 Signs You Need a Hyaluronic Acid Serum is a useful place to self-diagnose.

With the foundation firmly in place, the next logical question becomes: if hyaluronic acid already does all of this, what exactly is sodium hyaluronate - and does it do something different?

What Is Sodium Hyaluronate and How Is It Different?

This is the section that matters most for anyone standing in a shop aisle or scrolling a product page wondering why their “hyaluronic acid serum” lists “sodium hyaluronate” on the back. It is also the section where the sodium hyaluronate vs. hyaluronic acid question gets its most precise, evidence-backed answer.

Sodium hyaluronate is the sodium salt form of hyaluronic acid. It is derived directly from HA - it is not a separate, unrelated ingredient, but rather a specific molecular form of the same compound. On a skincare label, it appears under its INCI name: Sodium Hyaluronate. You may also occasionally see it listed as “hyaluronic acid (as sodium hyaluronate),” “hyaluronate sodium,” or “hyaluronic acid sodium salt” - all referring to the same thing.

The relationship between the two is important to understand. Sodium hyaluronate is not a cheap substitute for hyaluronic acid, nor is it a watered-down version. It is, in many formulation contexts, actually the preferred form to use - and the reason comes down to molecular weight.

Molecular weight is the defining difference between these two ingredients. Hyaluronic acid in its standard form is a high molecular weight molecule. Its large molecular size means it cannot penetrate through the skin’s surface. Instead, it sits at or just above the stratum corneum - the outermost layer of the skin - forming a moisture-retaining film that delivers immediate visible plumping and helps prevent transepidermal water loss. The results are fast and tactile: your skin feels smoother and looks more hydrated almost immediately.

Sodium hyaluronate has a significantly lower molecular weight than standard hyaluronic acid. Because its molecules are smaller, they can penetrate through the epidermis - the top layer of the skin - and deliver hydration from within the deeper skin layers rather than just at the surface. As Healthline confirms, in their medically reviewed article by Dr. Sara Perkins, MD: “Sodium hyaluronate has a lower molecular weight than hyaluronic acid. It’s small enough to penetrate the epidermis, or top layer of the skin. In turn, it can improve hydration from the underlying skin layers.”

This distinction has real implications for how skin responds over time. Surface-level hydration from high molecular weight HA provides instant, visible results - ideal for that immediate plumping effect. Deeper hydration from sodium hyaluronate supports more lasting moisture from within, addressing dehydration at the source rather than masking it at the top. For chronically dehydrated skin - the kind that drinks up product and still feels tight an hour later - that deeper action is particularly valuable. If dehydrated skin is a concern for you, the Skincare Routine for Dehydrated Skin guide covers the full picture.

Sodium hyaluronate also has a meaningful formulation advantage over pure hyaluronic acid. It is more stable in cosmetic formulas - less susceptible to oxidation and more consistent in its performance over the shelf life of a product. This is one of the primary reasons that sodium hyaluronate appears on INCI lists far more frequently than “hyaluronic acid.” It survives the formulation process better and delivers reliable, repeatable results from the first use to the last drop.

Did You Know? The ingredient listed as “hyaluronic acid” on many skincare labels is often sodium hyaluronate. Both names can legally and accurately describe the same source ingredient - the difference lies in molecular form, not in quality or efficacy. A product marketed as a hyaluronic acid serum that lists sodium hyaluronate on the INCI is not mislabelling anything. It is simply using the most stable, effective form of the molecule in its formula.

There is one more form worth introducing here: hydrolyzed sodium hyaluronate. This is sodium hyaluronate that has been broken down further into even smaller molecular fragments. Its extremely small molecular size allows it to penetrate deepest of all - reaching the lower layers of the epidermis where standard sodium hyaluronate cannot. It represents the third level in the molecular weight spectrum, providing the most durable, lasting hydration layer of the group.

Understanding sodium hyaluronate individually sets the stage for the comparison that most readers came here for - a direct, side-by-side look at how these two forms of the same molecule differ in practice, and what that means for your skin.

Sodium Hyaluronate vs. Hyaluronic Acid: The Key Differences Explained

At this point, both ingredients have been defined clearly on their own terms. Now it is time to put them side by side and answer the question directly. The sodium hyaluronate vs. hyaluronic acid comparison comes down to five key factors: source, molecular weight, where in the skin they work, the type of results they deliver, and how they behave in a formula.

Source and origin: Both sodium hyaluronate and hyaluronic acid come from the same origin. Hyaluronic acid is a naturally occurring molecule found in the human body and produced commercially via bacterial fermentation. Sodium hyaluronate is derived directly from hyaluronic acid - it is its sodium salt form. They share the same source material; the difference is in how that material is processed and what molecular form it takes in the final ingredient.

Molecular weight: This is the crux of the entire comparison. Hyaluronic acid in its standard, unmodified form is a high molecular weight molecule - a large, complex chain of sugar units. Sodium hyaluronate is a lower molecular weight form of the same molecule. The difference in size is significant enough to completely change how each one behaves on and in the skin. As Medical News Today notes in its medically reviewed overview: “Hyaluronic acid works better at hydrating the surface of the skin, whereas sodium hyaluronate can reach deeper layers, due to its lower molecular weight.”

Where in the skin each one works: Hyaluronic acid works predominantly at the skin’s surface. Its large molecules cannot penetrate the stratum corneum, so it stays where it lands - forming a moisture film on top of the skin that delivers instant plumping, smoothed texture, and visible surface hydration. Sodium hyaluronate, with its smaller molecular size, is able to move through the outer layer of the skin and into the epidermis below. It delivers hydration from within the skin layers rather than just from above.

Type and timing of results: Hyaluronic acid delivers fast, visible, tactile results from the moment it touches the skin. The plumping effect is immediate. Sodium hyaluronate works more deeply and cumulatively - its hydrating effect builds over time as it consistently replenishes moisture within the skin’s structure. Neither is “better” in an absolute sense. They complement each other, which is precisely why the most effective formulas use both together.

Stability in formula: Sodium hyaluronate is more chemically stable than pure hyaluronic acid. It is less prone to oxidation and retains its efficacy more consistently across the shelf life of a product. This is a key reason why sodium hyaluronate appears on INCI lists so frequently - formulators favour it because it performs reliably from batch to batch, and from the first application to the last.

On the question of labelling: A product that features “hyaluronic acid” prominently on its packaging may list “sodium hyaluronate” on the INCI - and this is completely correct. Sodium hyaluronate is the sodium salt of hyaluronic acid and is accurately described as a form of it. What matters more than the front-of-pack claim is where the ingredient appears on the full INCI list, and whether the formula contains more than one molecular form for multi-level coverage.

Here is a structured breakdown to make this concrete and scannable:

Hyaluronic Acid (High Molecular Weight)

Source: Naturally occurring; also sourced via fermentation
Molecular size: Large
Where it works: Surface of the skin (stratum corneum)
Primary function: Instant plumping, moisture film, immediate visible hydration
Speed of results: Fast - visible from first use
Best for: Immediate hydration boost, smoothed texture, visible plumping

Sodium Hyaluronate (Lower Molecular Weight)

Source: Derived from hyaluronic acid (sodium salt form)
Molecular size: Smaller
Where it works: Penetrates into the epidermis
Primary function: Deep, lasting hydration from within the skin’s layers
Speed of results: Cumulative - builds over consistent use
Best for: Long-term hydration, dehydrated skin, stable formulation

Can they be used together? Absolutely - and this is the gold standard. A formula that combines both forms hydrates at multiple depths simultaneously: surface plumping from hyaluronic acid, deeper and more lasting moisture from sodium hyaluronate. The INKEY Hyaluronic Acid Serum is a prime example of this multi-molecular approach in action - its INCI list confirms both Sodium Hyaluronate and Hyaluronic Acid within the top half of the ingredient list, meaning both are present in meaningful concentrations.

The short answer to the perennial question: sodium hyaluronate and hyaluronic acid share the same origin, but they are different forms of the same molecule. Think of sodium hyaluronate as the smaller, deeper-working sibling. The best formulations use both - and some go further. Browse the full Hyaluronic Acid collection to see which INKEY products carry both.

The comparison between the two headline forms is now clear. But the full hyaluronic acid family is actually larger than just these two - and understanding all four forms is what separates a casual skincare reader from someone who can genuinely decode a label and know what they are getting.

The Full Hyaluronic Acid Family: All Four Forms You Will See on Labels

Most skincare brands talk about “hyaluronic acid” as a single ingredient. A few mention sodium hyaluronate. Fewer still explain that there are actually four distinct forms of the HA molecule that appear in skincare formulations - each one working at a different depth in the skin. Knowing all four is what makes you a genuinely informed skincare shopper.

The four forms exist on a spectrum of molecular size. From largest to smallest: hyaluronic acid, sodium hyaluronate, hydrolyzed sodium hyaluronate, and sodium hyaluronate crosspolymer (which operates differently - more on that shortly). Each penetrates to a different level of the skin, meaning a formula that contains all four is simultaneously hydrating at every accessible depth. This is what the term “multi-molecular” means in skincare - and it is not marketing language. It is the most accurate technical description of a genuinely layered hydration strategy.

1. Hyaluronic Acid (High Molecular Weight)

This is the original form, the one the body naturally produces, and the one whose name appears on the front of countless products. As established, its large molecular size means it works at the skin’s surface - it cannot penetrate the stratum corneum. What it does there is significant: it forms a transparent, lightweight moisture-retaining film that immediately plumps the appearance of the skin, smooths the texture, and reduces water loss from the surface. The results are immediate and visible. Skin looks more hydrated and fuller within minutes. For anyone whose primary concern is that instant, fresh-faced hydration look, high molecular weight HA delivers it reliably and consistently.

2. Sodium Hyaluronate (Low-to-Medium Molecular Weight)

This is the most commonly used form in commercial skincare formulations, for two reasons: it penetrates deeper than high molecular weight HA, and it is more stable in a formula. Its smaller molecule size allows it to move through the outer layer of the skin and into the epidermis beneath, delivering hydration where the skin’s structure can hold onto it. The hydrating effect is less immediately dramatic than surface-level HA but more durable - it supports skin moisture over time rather than delivering a single-use hit. It is also the form you are most likely to see on an INCI list regardless of what the product’s packaging says, because formulators consistently choose it for its performance and reliability.

3. Hydrolyzed Sodium Hyaluronate (Very Low Molecular Weight)

Hydrolyzed sodium hyaluronate is sodium hyaluronate that has been broken down - hydrolyzed - into even smaller molecular fragments. The result is an ingredient with an extremely low molecular weight, capable of penetrating more deeply than any other form of HA used topically. It reaches the lower layers of the epidermis, providing hydration at a level that neither hyaluronic acid nor standard sodium hyaluronate can access. This makes it particularly valuable for skin that experiences persistent, deep-seated dehydration - the kind that does not resolve with surface-level hydration alone. Its hydrating effect is cumulative and lasting, contributing to a more durably moisturised skin structure over time, as documented in research reviewed by DermCollective.

4. Sodium Hyaluronate Crosspolymer (Modified Form)

This is the most functionally distinct of the four forms. Sodium hyaluronate crosspolymer is a modified version of sodium hyaluronate in which the molecular chains have been cross-linked - essentially bonded together into a three-dimensional network. This crosslinked structure fundamentally changes how the ingredient releases moisture. Rather than delivering its hydrating effect in a single burst at application, sodium hyaluronate crosspolymer acts as an extended-release system - gradually releasing moisture into the skin over a prolonged period. The practical effect is skin that stays hydrated for longer after each application, rather than requiring constant reapplication to maintain the benefit.

The Multi-Molecular Advantage ; A formula that contains more than one form of hyaluronic acid hydrates at multiple depths simultaneously - surface, epidermal, and deeper epidermal layers - while also extending the duration of that hydration. This is why multi-molecular HA formulas consistently outperform single-form approaches in clinical assessments.

The Ectoin Hydro-Barrier Serum is one of the few formulas that contains all four forms within a single product. Its INCI list confirms: Hydrolyzed Sodium Hyaluronate, Sodium Hyaluronate, Sodium Hyaluronate Crosspolymer, and Hyaluronic Acid - all present, all working at different depths and durations simultaneously. This level of formulation depth is uncommon in the mass skincare market, and it represents a genuinely meaningful difference in how comprehensively the formula addresses hydration.

The INKEY Hyaluronic Acid Serum uses a 2% Multi-Molecular Hyaluronic Acid complex that combines both Sodium Hyaluronate and Hyaluronic Acid - confirmed on its INCI list - working at different molecular weights to hydrate both at the surface and within the epidermis.

For readers curious about what ectoin itself contributes to the Ectoin Hydro-Barrier Serum alongside the full HA family, the What Is Ectoin guide covers the ingredient in full detail.

Understanding the four forms of HA is only half the picture. The other half is being able to identify them on a label - which requires knowing how to read an INCI list in the first place.

How to Read Your Skincare Labels: Decoding the INCI List Like a Pro

The INCI list - the International Nomenclature of Cosmetic Ingredients - is the standardised global system used to name every ingredient in every skincare product sold legally in the UK and US. It is the list on the back of every product, typically in small print, that most people ignore and a few people obsess over. INKEY’s brand name comes directly from this list - it is a declaration of transparency, a commitment to making the INCI list readable and meaningful for everyone, not just cosmetic chemists.

Here is how it works, and how to use it to your advantage when shopping for hyaluronic acid products specifically.

Ingredients are listed in descending order of concentration. The ingredient present in the highest amount appears first. Water (listed as “Aqua” or “Water/Aqua/Eau”) appears first on most water-based serums because it is, by volume, the dominant ingredient. As you move down the list, concentrations decrease. Ingredients in the last five entries are typically present at trace levels - often below 1%.

This means position matters enormously. An ingredient listed in the first half of an INCI list is present in a meaningful concentration. The same ingredient listed in the final three or four positions may be present only as a trace - technically there, but unlikely to deliver a significant benefit. When evaluating any HA product, look for where on the list the HA-family ingredients appear, not just whether they are there at all.

For the INKEY Hyaluronic Acid Serum, the INCI reads: Water (Aqua/Eau), Propanediol, Sodium Hyaluronate, Glycerin, Butylene Glycol, Phenoxyethanol, Ammonium Acryloyldimethyltaurate/VP Copolymer, Leuconostoc/Radish Root Ferment Filtrate, Hyaluronic Acid… Both Sodium Hyaluronate and Hyaluronic Acid appear in the top half of the list, confirming that both are present at meaningful, active concentrations - not token amounts. This is exactly what to look for in a quality multi-molecular HA formula.

For the INKEY Ectoin Hydro-Barrier Serum, all four forms - Hydrolyzed Sodium Hyaluronate, Sodium Hyaluronate, Sodium Hyaluronate Crosspolymer, and Hyaluronic Acid - appear in the INCI, confirming that the multi-molecular approach extends across all four molecular sizes simultaneously.

How to spot HA derivatives on any label:

Look for any of these names: Hyaluronic Acid, Sodium Hyaluronate, Hydrolyzed Sodium Hyaluronate, Sodium Hyaluronate Crosspolymer, Hyaluronate Sodium, Hyaluronic Acid Sodium Salt
Check where they appear on the list - higher is more concentrated
Count how many forms are present - more forms means multi-molecular coverage
If only one form appears near the bottom of the list, the actual active concentration is likely minimal

The common shopper confusion - addressed directly: A product marketed as a “hyaluronic acid serum” may list only “sodium hyaluronate” on the INCI and not “hyaluronic acid” as a separate entry. This is not misleading, and it is not a bait-and-switch. Sodium hyaluronate is the sodium salt of hyaluronic acid and is entirely accurately described as a form of it. The brand is using the form most suitable for the formula. What matters is whether the concentration is meaningful and whether the formula uses multiple forms for layered coverage.

What to look for on a label - a practical checklist:

Does the formula contain more than one form of HA or sodium hyaluronate? Multi-molecular coverage is the gold standard.
Where do the HA-family ingredients appear on the INCI list? Higher means more concentration and more meaningful benefit.
Does the routine also include a moisturiser as a follow-up step? HA is a humectant - it draws water in, but a moisturiser is needed to seal it there.
Is sodium hyaluronate listed in the last three to four ingredients? If so, the concentration is likely negligible regardless of the front-of-pack claims.

For further reading on how hydration and moisturisation differ - and why you need both steps - visit The Difference Between Moisturising and Hydrating. And to browse every INKEY product formulated with hyaluronic acid, visit the Hyaluronic Acid collection.

Armed with the ability to decode any label, the final practical step is understanding how to actually use these products together in a routine - and which INKEY formula is right for your specific skin concern.

INKEY Serums That Use Both: Building a Hydration-First Routine

Knowledge of the ingredient science only becomes useful when it translates into a routine you can actually follow. This section covers both INKEY hero products in practical detail - what is in them, what they deliver, how to use them, and how to decide which one (or both) belongs in your routine.

Hyaluronic Acid Serum - from £9 / 30ml

The INKEY Hyaluronic Acid Serum is the foundational hydration step for all skin types. At £9 for 30ml, it is one of the most accessible entry points into multi-molecular HA skincare available - and the formulation punches considerably above its price point.

The 2% Multi-Molecular Hyaluronic Acid complex confirmed in the formula contains both Sodium Hyaluronate and Hyaluronic Acid as distinct INCI entries, appearing in the top half of the ingredient list. This means both forms are present at meaningful concentrations, delivering simultaneous hydration at the surface and within the epidermis. The formula also contains Matrixyl 3000 Peptide, a well-researched peptide complex that supports the appearance of firmer, smoother-looking skin over time - adding an additional layer of skin benefit beyond hydration alone.

The clinical results back up the formulation: 82% of users agreed their skin felt firmer, smoother, and more elastic after four weeks of use, and 86% agreed the serum is quick-absorbing, lightweight, and non-tacky. It has earned recognition from Allure Best of Beauty 2022, CEW 2023, Glamour, and Get The Gloss Gold - a consistent track record across independent editorial evaluation.

How to use it: Apply morning and evening to slightly damp, cleansed skin. A pea-sized amount is enough for the full face. Pat - do not rub - the serum gently into the skin. Follow with any targeted treatments, then your moisturiser, and SPF in the morning. The damp-skin tip is important: applying to skin that still holds a little moisture from cleansing gives the humectants something immediate to draw from, maximising their effect.

This serum is the right choice for:

All skin types seeking daily hydration
Anyone new to HA who wants a reliable, proven formula
Skin that feels dehydrated, tight, or lacks bounce
Anyone building a simple, high-performance routine without complexity

Ectoin Hydro-Barrier Serum - £15 / 30ml

The Ectoin Hydro-Barrier Serum is the more specialised of the two. At £15, it targets a specific skin concern - compromised, sensitive, or barrier-disrupted skin - and it approaches that concern from multiple angles simultaneously.

The formula contains all four forms of hyaluronic acid: Hydrolyzed Sodium Hyaluronate, Sodium Hyaluronate, Sodium Hyaluronate Crosspolymer, and Hyaluronic Acid - each working at a different molecular weight and skin depth. On top of that 2.5% Multi-Molecular Hyaluronic Acid complex sits 2% Ectoin - a naturally occurring extremolyte originally found in microorganisms that survive extreme environmental conditions. Ectoin provides dual action: it strengthens the skin barrier while simultaneously hydrating, making it particularly valuable for skin that is reactive, sensitised, or showing signs of a compromised barrier - redness, tightness, flaking, or sensitivity to products that were previously well tolerated. For a full breakdown of ectoin as an ingredient, visit What Is Ectoin. The formula is completed by a 1% Barrier Blend of three ceramides, which work to reinforce the skin’s natural lipid barrier structure, reducing moisture loss and improving long-term resilience.

The clinical results are compelling: the serum is clinically proven to hydrate and strengthen the skin barrier in as little as 15 minutes. Visible bounce is restored in three days. And across four weeks of consistent use, it visibly improves five signs of a compromised skin barrier. It holds a 4.6-star average across over 400 reviews.

How to use it: Apply morning and evening to cleansed skin as the first serum step. If layering with additional serums, the Ectoin Serum goes on first - its lighter molecular structure allows maximum absorption before heavier formulas are applied. Follow with treatments, then moisturiser.

This serum is the right choice for:

Sensitive, reactive, or easily irritated skin
Skin that is visibly compromised - flaky, red, tight, or barrier-stressed
Dehydrated skin that needs both deep hydration and structural barrier repair
Anyone using strong actives (retinol, acids) who needs a robust hydration and barrier buffer

Using both serums together: The two products are complementary, not redundant. If using both, apply the Ectoin Hydro-Barrier Serum first, then follow with the Hyaluronic Acid Serum for an additional layer of multi-molecular hydration. The combination delivers hydration at every depth the skin can access - surface, epidermal, and deep epidermal - while simultaneously supporting barrier integrity through ectoin and ceramides.

Or, if choosing just one:

For daily hydration for all skin types: Hyaluronic Acid Serum
For sensitive, reactive, or barrier-compromised skin: Ectoin Hydro-Barrier Serum
For maximum hydration and barrier support combined: both, layered in order

Both serums pair well with a wide range of other actives. For guidance on specific ingredient combinations, these guides cover the most common questions:

With both products and routine guidance in place, the final section addresses the questions that come up most frequently - concise, direct answers to the things people search for most when trying to understand sodium hyaluronate vs. hyaluronic acid.

Your Questions Answered: Sodium Hyaluronate and Hyaluronic Acid FAQ

Is sodium hyaluronate the same as hyaluronic acid?

They come from the same source - sodium hyaluronate is the sodium salt form of hyaluronic acid, derived directly from it. They are related but not identical. The critical difference is molecular weight: hyaluronic acid is larger and works at the skin’s surface, while sodium hyaluronate is smaller and penetrates into the epidermis for deeper hydration. Both are humectants. The best formulas use both together for multi-level coverage.

Is sodium hyaluronate better than hyaluronic acid?

Neither is categorically better. They work at different depths and deliver different types of results. Hyaluronic acid provides instant surface plumping and an immediate visible moisture film. Sodium hyaluronate penetrates deeper for lasting hydration from within. The gold standard in formulation is combining both - and ideally all four molecular forms - for simultaneous action across every accessible layer of the skin.

What does sodium hyaluronate actually do for skin?

It hydrates the skin from within the epidermis. As a humectant, it attracts water molecules and holds them in the deeper skin layers, reducing dehydration, improving skin texture and feel, and supporting a healthy, plumped-looking complexion over consistent use. For a complete guide to building sodium hyaluronate into your routine, the Skincare Routine for Dehydrated Skin covers the full approach.

Why does my product say “hyaluronic acid” on the front but list “sodium hyaluronate” on the INCI?

This is completely standard and accurate labelling. Sodium hyaluronate is derived from hyaluronic acid and is its most commonly used cosmetic form. A product can accurately describe itself as a hyaluronic acid serum even when the INCI lists sodium hyaluronate - they refer to the same ingredient family, with sodium hyaluronate being the more stable, penetration-capable molecular form. What matters is where the ingredient appears on the INCI list and whether the formula contains multiple forms.

What is hydrolyzed sodium hyaluronate?

Hydrolyzed sodium hyaluronate is sodium hyaluronate that has been broken down into even smaller molecular fragments through a hydrolysis process. Its very low molecular weight allows it to penetrate more deeply than standard sodium hyaluronate - reaching the lower layers of the epidermis where the other forms cannot access. It provides the deepest and most durable layer of hydration available from topical HA-family ingredients, making it a particularly valuable addition to formulas designed for persistently dehydrated or compromised skin.

Can you use sodium hyaluronate every day?

Yes - without reservation. Both sodium hyaluronate and hyaluronic acid are exceptionally well-tolerated, non-irritating, and designed for daily use morning and evening. There is no adjustment period, no risk of sensitivity, and no meaningful ceiling on frequency of use. They are safe for all skin types including sensitive and blemish-prone skin, and are considered safe during pregnancy and breastfeeding.

What is sodium hyaluronate crosspolymer?

Sodium hyaluronate crosspolymer is a modified, cross-linked form of sodium hyaluronate in which the molecular chains have been bonded into a three-dimensional network. This crosslinked structure slows the release of moisture, turning the ingredient into an extended-release hydration system. Rather than delivering moisture in a single burst at application, it keeps the skin hydrated over a prolonged period. The INKEY Ectoin Hydro-Barrier Serum contains sodium hyaluronate crosspolymer as one of its four HA forms.

Should hyaluronic acid be applied to wet or dry skin?

Always slightly damp skin. Applying HA-family ingredients immediately after cleansing - before the skin has fully dried - gives the humectants direct access to ambient moisture to draw from, significantly increasing their effectiveness. On completely dry skin in a low-humidity environment, humectants may draw moisture upward from the deeper skin layers, which is why sealing them in with a moisturiser as the next step is always essential, not optional.

Do I need both the Hyaluronic Acid Serum and the Ectoin Serum?

Not necessarily - it depends on your skin concern. The Hyaluronic Acid Serum covers daily hydration for all skin types effectively on its own. The Ectoin Hydro-Barrier Serum is the choice for sensitive, dehydrated, or barrier-compromised skin that needs hydration and barrier repair working together. Used in combination - Ectoin Serum first, HA Serum second - they provide maximum multi-molecular hydration alongside barrier strengthening and ceramide support. Whether you need one or both comes down to how your skin is behaving right now.

What You Now Know About Sodium Hyaluronate vs. Hyaluronic Acid

The sodium hyaluronate vs. hyaluronic acid question has a genuinely useful answer - one that makes you a more informed skincare shopper every time you read a label.

Here is the short version of everything this guide covered: Sodium hyaluronate is the sodium salt form of hyaluronic acid. It is derived from it, related to it, but distinct in one critical way - molecular weight. Hyaluronic acid, with its larger molecules, works at the skin’s surface to deliver immediate plumping and a moisture-retaining film. Sodium hyaluronate, with its smaller molecules, penetrates into the epidermis to deliver deeper, more lasting hydration from within. Hydrolyzed sodium hyaluronate goes deepest of all. Sodium hyaluronate crosspolymer extends the duration of hydration through a slow-release mechanism. None of these forms is better than another in isolation. Together, in the right formula, they are the gold standard.

When reading any skincare label: “sodium hyaluronate” listed under a product marketed as a “hyaluronic acid serum” is not a mislabelling. It is the most stable and effective form of the molecule in cosmetic use. What matters is where it appears on the INCI list and how many forms are present.

Two INKEY products to consider based on your skin’s needs:

Hyaluronic Acid Serum - from £9 / 30ml. Contains both Sodium Hyaluronate and Hyaluronic Acid in a 2% multi-molecular complex. For all skin types, daily use.
Ectoin Hydro-Barrier Serum - £15 / 30ml. Contains all four forms of hyaluronic acid, plus 2% Ectoin and 3 Ceramides. For sensitive, reactive, or barrier-compromised skin.

For the complete deep-dive on hyaluronic acid and its full range of skin benefits, visit the Hyaluronic Acid ingredient guide.

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