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Statistic from clinical study from customers using Hyaluronic Acid Serum

How to layer Hyaluronic Acid Serum in your routine

woman's face with results from recent clinical trial of customer using Hyaluronci acid serum

Bottle of skincare product with droplet on finger and usage instructions.

Before & after using Hyaluronic Acid Serum

3 different sizes of Hyaluronic Acid Serum bottles and usage estimate (30ml = 60 uses, 60ml = 120 uses, 100ml = 180 uses)

Model applying Hyaluronic Acid Serum to her face

Skin /
Skincare Sets /
Supersize Hyaluronic Acid Serum 100ml Duo

Supersize Hyaluronic Acid Serum 100ml Duo | The INKEY List

Name: Supersize Hyaluronic Acid Serum 100ml Duo
Brand: The INKEY List UK
SKU: BUNTILUK080
Availability: InStock
Rating: 4.7 (2958 reviews)

Double up on our non-tacky hydrating serum, now 3x the size!

4.7

Rated 4.7 out of 5 stars

4.7 Stars (2,958 Reviews)

£41.80 / 2 full-size products

Free Deluxe Mini Sample* Claim at cart

Worth 205 Points

What you get: A lightweight hydrating serum that delivers instant and lasting hydration, leaving your skin plump, smooth, and ready for the day.

Why it works: 2% Multi-Molecular Hyaluronic Acid holds up to 1000x its weight in water, delivering intense hydration across multiple layers of skin. Matrixyl™ 3000 Peptide helps to pump, firm and smooth skin.

How it feels: Lightweight and hydrating. No greasiness, stickiness, or tackiness.

When to use: AM & PM. Use this moisturising serum right after your cleanse.

This duo includes: 2x Hyaluronic Acid Serum (100ml)

Suitable for:

All skin types
Sensitive skin
Pregnancy & breastfeeding
Teen approved

Targets:

Dehydrated skin
Fine lines & wrinkles
Damaged skin barrier

How to Use in a routine

Use AM and PM. On damp, cleansed skin, apply a pea-sized amount to face and neck. Gently pat in.

Follow with

Treatments → moisturiser.

Finish with SPF in your AM routine.

INKEY Tip

Apply to damp skin to lock in hydration.

Also helps other products absorb better—no pilling here.

Heads up

When adding new products to your skincare routine, we always recommend patch testing. Learn more here.

Storage

Store in a cool, dry place (15–25°C). Keep out of direct sunlight. Avoid eyes. For external use only. Keep out of reach of children.

Key Claims

82%

agreed their skin felt firmer and more elastic after 4 weeks of use*

86%

agreed the serum is non-tacky*

Clinically proven to deliver instant hydration*
Contributes to improved skin barrier by reducing water loss*

*4-week independent clinical study of 22 people under dermatological control

**4-week independent consumer study of 22 people under dermatological control

Ingredients

2% Multi-Molecular Hyaluronic Acid: Hydration powerhouse. This moisture magnet pulls water into the skin and holds it there—helping to keep skin looking plump, smooth, and healthy.
Matrixyl 3000™ Peptide: Targets the look of fine lines and supports firmer-looking skin.

Water (Aqua/Eau), Propanediol, Sodium Hyaluronate, Glycerin, Butylene Glycol, Phenoxyethanol, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Leuconostoc/Radish Root Ferment Filtrate, Hyaluronic Acid, Carbomer, Sodium Lactate, Polysorbate 20, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1.

FAQs

WHEN TO USE Apply Hyaluronic Acid Serum after cleansing, on damp skin. Wait 30-60 seconds, then follow with other treatments.

WHY FIRST AFTER CLEANSING? This serum absorbs best on damp skin and creates a hydration barrier for products that follow. It also soothes skin and balances pH.

SHOULD I HYDRATE BEFORE A TONER? Yes, it helps the toner and other products absorb better by working deep beneath the skin’s surface.

CAN IT BE USED WITH OTHER PRODUCTS? Yes, it works with everything (including actives like Retinol & AHAs) and enhances the effectiveness of other products.

DO I NEED A MOISTURISER? Hydrators (like Hyaluronic Acid) add water to the skin, while moisturisers lock it in. You may need both, depending on your skin type.

WHO IS IT FOR? All skin types, especially dry or dehydrated skin, and mature skin needing a hydration boost.

IS IT AN AHA? No, it hydrates, not exfoliates.

WHAT % OF HYAURONIC ACID IS THERE %? 2% Multi-Molecular Hyaluronic Acid.

WHAT TYPE OF HYALURONIC ACID? Multi-Molecular, targeting different skin layers for better hydration.

WHAT IS THE PH LEVEL? 6.21

HOW LONG TO SEE RESULTS? Around 6 weeks. Consistency matters—don’t overuse.

IS IT VEGAN? Yes, certified by The Vegan Society.

IS IT SAFE FOR PREGNANT/BREASTFEEDING? Yes.

CAN I USE WITH MEDICATION? Consult your doctor to be sure.

No BS Skincare

Skincare can be confusing.

So we cut the BS, and get straight to the point. We simplify the INCI list - commonly known as the ingredients list, that every skincare product has. That’s also where we get our name from. We’re The INKEY List - here to help you get better skin with real knowledge and formulas that deliver. No BS. No hype. Just effective, science-backed skincare that does what it says it will. We show you what your skin needs, not what’s trending. Whether you’re new to skincare or have a solid routine, we’ve always got your back with innovation, education and clinically-proven results.

All at a price that makes sense.

INKEY. No BS, just better skin.

We are B CORP. Our products are formulated with responsibly sourced ingredients, and packaged with 100% recyclable materials. Skin needs love, but so does our planet.

Carbon Net-Zero. All our emissions are offset annually through planet friendly projects with a focus on education.

Approved under the Cruelty Free International Leaping Bunny programme.

100% of our packaging is recyclable. Learn how to recycle your INKEY List products.

Certified by The Vegan Society

This product is;

Dermalogically tested

Clinically tested

Fragrance-free

Gluten-free

Pregnancy & Breastfeeding safe

Awards & Features

The cult-favourite, hydration serum that hero that kicked off the INKEY obsession

Clinically proven to deliver instant hydration – but it doesn’t stop there clinically proven to plumps, firms, smooths and boost the efficacy of every product you layer on top – and its only £22 - its your overpriced serums worst nightmare.

Instantly hydrates & plumps
Boosts absorption of other products
Lightweight, non-sticky formula. Just £22

Delivery info

Standard tracked delivery (Evri)

£3.99 or FREE on your first order & orders over £30
(2-5 working days*)

Express tracked delivery (Evri)

£5.95 or FREE on orders £50+
(Up to 2 working days if ordered before 8pm, excluding weekends*)

*Find out more about delivery options and delivery area restrictions here.

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our trusted couriers

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More Blogs

"I decided to try Hyaluronic Acid Serum as I'm struggling with acne dry skin from medications. I've been using it for more than a year and my skin is glowing and feels softer than ever! I would definitely recommend this product if you want change your skin for better!"

Katarzyna
"You have been a part of the past 2 years of my skincare journey. Thank you INKEY!"

Keanu
"I’ve used INKEY products religiously and my skin is just amazing! This is before I started and what it is like now. My skin's never been better!"

Adelle
"The INKEY List is the only skincare that's helped my acne-prone skin due to my polycystic ovaries". Lauren has been using Oat Cleansing Balm, Salicylic Acid Cleanser, Hyaluronic Acid Serum, Succinic Acid Treatment and Omega Water Cream since December 2022."

Lauren
"Just wanted to say I’ve been using your brand for just over a month and the products have really helped with my acne and the scarring! They are amazing and the results are incredible."

Amy
"I used the online askINKEY service and chose the Hyaluronic Acid Serum, the Succinic Acid Treatment, and the Omega Water Cream. These are my results after 3 months ❤️ "

Chloe
"Your products have helped me become so much more confident and happy in my skin!"

Tatiana

4.7

Rated 4.7 out of 5 stars

Based on 2,958 reviews

Total 5 star reviews: 2.4k Total 4 star reviews: 424 Total 3 star reviews: 68 Total 2 star reviews: 29 Total 1 star reviews: 42

Reviews Summary

Customers say this serum absorbs quickly and provides instant hydration. Many reviews mention its lightweight, non-sticky texture that layers well with other products. The serum leaves skin feeling soft, smooth, and plump. Frequent users appreciate its simple, effective formula and note it works well for various skin types. While some mention the packaging could be improved, most are repeat purchasers who consider this a daily essential.

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2,958 reviews

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Mariana S.
Verified Buyer
Reviewing
Hyaluronic Acid Serum - 60ml
I recommend this product
Age Range 45 - 54
Skin Type Combination
Skin Concerns Plumping, Fine Lines and Wrinkles, Under Eye Circles
Sensitive Skin Friendly? Yes
Rated 5 out of 5 stars
3 days ago
Deep Hydration and Smooth Skin with Hyaluronic Acid
I’ve bought this Hyaluronic Acid Serum several times now, and it’s always a winner. The 60ml bottle lasts a while, and the serum absorbs quickly, leaving my skin plump, soft, and refreshed. I’ve noticed improved elasticity and a healthy glow after consistent use. Highly recommended!
Was this helpful?
Hilary C.
Verified Buyer
Reviewing
FREE Hyaluronic Acid Serum 30ml
I recommend this product
Rated 5 out of 5 stars
4 days ago
Never without this product
Love this wouldn't be without it ❤️
Was this helpful?
Reema R.
Verified Buyer
Reviewing
FREE Hyaluronic Acid Serum 60ml
I recommend this product
Rated 5 out of 5 stars
5 days ago
Hydrates my skin!!
My skin was super dry and flakey before I used this product - genuinely such a life saver. Use it after washing your face and leave it a little bit damp (not wet) - I feel like
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Supersize Hyaluronic Acid Serum 100ml Duo | The INKEY List

Suitable for:

Targets:

How to Use in a routine

Key Claims

Ingredients

FAQs

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The cult-favourite, hydration serum that hero that kicked off the INKEY obsession

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Supersize Hyaluronic Acid Serum 100ml Duo | The INKEY List

Suitable for:

Targets:

How to Use in a routine

Key Claims

Ingredients

FAQs

No BS Skincare

Awards & Features

The cult-favourite, hydration serum that hero that kicked off the INKEY obsession

Delivery info

Caffeine Eye Cream

Oat Cleansing Balm - 150ml

Polyglutamic Acid Serum

Omega Water Cream - 50ml

Still not sure?

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