Hyaluronic acid (HA) is a humectant: it attracts and holds water, which is why it appears in so many hydrating serums. The serums below all use it, but in different forms and alongside different ingredients, from an oil-free gel with vitamin B5 to blends with peptides and vitamin C. Here is how four of them compare, and how to apply HA so it does its job.
The four serums side by side
| Serum | Hyaluronic acid (as described) | Also in the formula | Texture or role | How to apply |
|---|---|---|---|---|
| SkinCeuticals Hydrating B5 Gel | Pure hyaluronic acid | Vitamin B5 (panthenol) | Watery, jelly-like, oil-free gel | 2 to 3 drops pressed into damp skin right after cleansing, morning and evening |
| Hydrinity Restorative HA Serum | Supercharged Hyaluronic Acid, Hydrinity's patented form | — | A hydrating base layer under more active serums | 3 to 4 drops on clean, slightly damp skin, morning and evening, before moisturizer |
| Hydrinity Renewing HA Serum | Hydrinity HA complex, a proprietary low-molecular-weight HA | Multi-peptide complex, niacinamide, stabilized vitamin C | Featherweight texture that absorbs immediately | 4 to 5 drops on clean skin, morning and evening, before moisturizer |
| SkinMedica HA5 Rejuvenating Hydrator | Five forms: time-release HA, sodium hyaluronate, uncross-linked HA, nano HA and cross-linked HA | VITISENSCE technology: Vitis flower stem cell antioxidants, a peptide complex and polysaccharides | Weightless, silky finish | Follow the directions on the label |
How to apply hyaluronic acid
- On damp skin. HA draws in water, and damp skin gives it water to work with. B5 Gel works especially well on skin that is still slightly wet, and Restorative HA Serum asks for slightly damp skin.
- Before moisturizer. Each serum here goes on before your moisturizer, and a moisturizer on top helps seal the hydration in.
- Morning and evening. HA serums suit twice-daily use, after cleansing.
- Under your actives. B5 Gel and Restorative HA Serum are made as a hydrating base under more active products, and Restorative helps buffer their effects.
Where SkinMedica HA5 fits
HA5 Rejuvenating Hydrator is hydration first: five forms of hyaluronic acid, including a time-release form for sustained hydration through the day, with VITISENSCE technology. Its weightless, silky finish immediately softens skin and diminishes the look of fine lines and wrinkles, and with continued use it helps skin hold on to moisture for a radiant-looking tone and texture. Choose it if hydration and a silky finish are the priority.
Hydrinity Renewing vs Restorative HA Serum
- Renewing HA Serum is the all-in-one. Hydrinity's low-molecular-weight HA complex is paired with a multi-peptide complex, niacinamide and stabilized vitamin C. It helps skin look plumper and more hydrated while improving the look of fine lines, uneven-looking tone and surface texture. It is a comprehensive single serum for anyone new to active serums, and it can be used with retinol in the evening, with the HA helping to buffer a retinol routine.
- Restorative HA Serum is the pure hydrator. Built around Hydrinity's patented Supercharged Hyaluronic Acid, it helps skin hold on to moisture and plumps the look of fine lines associated with dehydration. It suits every skin type, especially mature skin, and makes a hydrating base layer for routines with more active serums.
If you want one serum that does more than hydrate, choose Renewing. If you already use actives and want hydration underneath them, choose Restorative.
Where B5 Gel fits
SkinCeuticals Hydrating B5 Gel is the simplest formula here: pure hyaluronic acid with vitamin B5 (panthenol) in an oil-free gel that sinks in within seconds. It suits every skin type, especially oily, combination and blemish-prone skin, and it layers under any moisturizer, vitamin C or retinol routine. Press 2 to 3 drops into damp skin right after cleansing. If your next step is a vitamin C serum that goes on dry skin, give the gel a moment to sink in first.
Where HA fits in a routine
| Step | Morning | Evening |
|---|---|---|
| 1. Cleanse | Cleanser | Cleanser |
| 2. Hydrate | HA serum on damp skin | HA serum on damp skin |
| 3. Actives | Vitamin C serum, once the HA has sunk in | Retinol or a peptide serum |
| 4. Moisturize | Moisturizer | Moisturizer |
| 5. Protect | SPF, always last | — |
The general rule is thinnest to thickest: watery serums and gels first, creams last. When a label gives a specific order, follow the label.
HA beyond serums
- Cleanser: Hydrinity Prelude Facial Treatment Cleanser brings Hydrinity's HA complex to the cleansing step.
- Mist: Hydrinity HyaCyn Active Purifying Mist pairs stabilized hypochlorous acid with the HA complex, for refreshing hydration through the day.
- Moisturizer: ZO Hydrating Creme uses hyaluronic acid for water-binding hydration in a cream for normal to combination skin.
- Lips: Hydrinity Luxe Lip pairs the HA complex with peptides and plant-derived squalane.
- A soothing gel: SkinCeuticals Phyto Corrective Gel combines hyaluronic acid with cucumber, thyme and olive leaf extracts, for skin that feels sensitive and the look of redness.
How to choose
- Oily or combination skin that wants oil-free hydration: SkinCeuticals Hydrating B5 Gel.
- A pure hydrating base under active serums: Hydrinity Restorative HA Serum.
- One serum that hydrates and does more: Hydrinity Renewing HA Serum.
- A multi-form HA with a silky finish: SkinMedica HA5 Rejuvenating Hydrator.
Browse hyaluronic acid skincare, hydration and barrier support, ceramide skincare or the full Hydrinity range. For where a hydrating serum sits among your other steps, see how to layer skincare.
Related guides: SkinCeuticals vitamin C serums compared, retinol strengths explained and growth factor vs peptide serums.