Serum Syntax is published by U Beauty. This guide includes U Beauty products alongside others we think are worth knowing about, and it is not an independent review. Prices and formulations are as of September 2026.

Key Takeaways

• Forehead lines tend to be expression lines, so the serums most often compared for their look are built around peptides, a Retinoid, or both.

• Peptides, such as Acetyl Hexapeptide-8, may help soften the look of expression lines, and Retinoid serums tend to help with the look of fine lines and texture over weeks of consistent use.

• The SMOOTH Dynamic Wrinkle Defense Serum is designed to combine several peptides, including Acetyl Hexapeptide-8 and Copper Tripeptide-1, with two Retinol Esters in one formula for the face and neck.

• Prices on this list run from $24.99 to $248, so it’s worth comparing size and what each formula brings beyond its lead ingredient before committing to months of use.

• Daily broad-spectrum sunscreen, SPF 30 or higher per the AAD, is especially important alongside any Retinoid serum and can help keep new lines from looking more visible.

What Tends to Help the Look of Forehead Lines

Most forehead lines start as expression lines. They tend to show up where your brows lift, many times a day, for years, and dehydration or a lot of sun exposure can make them look more visible. The American Academy of Dermatology puts avoiding repetitive facial expressions and wearing sunscreen every day on its list of ways to help reduce premature skin aging.

So a serum for the look of forehead lines is really a choice between two ingredient routes, or a formula that combines them. Peptides, with Acetyl Hexapeptide-8 the best-known, have been studied for the look of lines set by repeated expression. Retinoids have the longer record for visibly smoother-looking fine lines and texture. Good hydration sits underneath both, because plumper-looking skin can make a crease appear more shallow.

We compared nine face serums on five things: the peptides named in the ingredient list, the Retinoid named in it, the hydrators that support them, how easily each fits a daily routine, and price for the size.

At a Glance

• HydroPeptide Power Serum: best for a peptide-only formula that brings several peptides into one step.

• The SMOOTH Dynamic Wrinkle Defense Serum: best for combining peptides and Retinol Esters in one serum for the face and neck.

• Biossance Squalane + Copper Peptide Rapid Plumping Serum: best for a hydrating Copper Peptide step with more peptides alongside.

• Paula’s Choice CLINICAL 1% Retinol Treatment: best for a Retinol formula that also lists peptides and a Vitamin C derivative.

• StriVectin Advanced Retinol Nightly Multi-Correct Serum: best for an evening Retinol step with Ectoin and Polyglutamic Acid.

• Peter Thomas Roth Retinol Fusion PM Night Serum: best for a short, silicone-based Retinol formula used at night.

• La Roche-Posay Retinol B3 Pure Retinol Serum: best for an evening Retinol and Niacinamide serum the brand describes as suitable for sensitive skin.

• Olay Retinol 24 MAX Night Smoothing Serum: best for a drugstore night serum with Retinol, Niacinamide, and a peptide.

• RoC RETINOL CORREXION Line Smoothing Night Serum Capsules: best for pre-measured single doses of Retinol.

How We Compared These Products

Every ingredient claim below was checked against the full ingredient list on each brand’s product page in September 2026. We did not test these products hands-on; this is a comparison of formulas, directions, and prices.

• Named peptides: a label that names Acetyl Hexapeptide-8, Palmitoyl Tripeptide-5, or a similar peptide tells you more about the formula’s intent for expression lines than a vague “peptide complex.”

• The Retinoid, by its ingredient-list name: Retinol and Retinol Esters, such as Retinyl Palmitate or Retinyl Linoleate, are different ingredients, and the name helps you plan how often to use the serum.

• Hydration support: Squalane, Glycerin, and Sodium Hyaluronate can help skin look plumper, which may make a forehead crease appear softer while the slower-acting ingredients do their work.

• Routine fit: some formulas are directed for morning and evening use, others for night only, and a build-up schedule matters for anyone new to a Retinoid.

• Price and size: forehead lines ask for consistent use over months, so the cost of each bottle, and how long it lasts, is part of the choice.

Forehead Line Serums Compared

1. HydroPeptide Power Serum

This lightweight, peptide-led face serum names more peptides in its ingredient list than any other formula here: Acetyl Hexapeptide-30, Dipeptide Diaminobutyroyl Benzylamide Diacetate, Palmitoyl Tripeptide-5, Palmitoyl Hexapeptide-19, and Hexapeptide-11, alongside Sodium Hyaluronate and Tetrahexyldecyl Ascorbate, an oil-soluble Vitamin C derivative. HydroPeptide directs a full pump onto clean face and neck before moisturizer, morning and night, followed by SPF in the morning. Several peptides plus a humectant may help soften the look of creases while keeping skin looking plump.

Best for: A peptide-only routine for the look of forehead and expression lines.

Key ingredients: Acetyl Hexapeptide-30, Palmitoyl Tripeptide-5, Sodium Hyaluronate, Tetrahexyldecyl Ascorbate.

Price: $160 (1 fl oz).

Worth knowing: No Retinoid is listed, so anyone seeking a Retinoid step would add it separately. Several citrus peel extracts and Vanilla Planifolia Fruit Extract appear in the ingredient list, which sensitive-skin readers may want to note.

2. U Beauty The SMOOTH Dynamic Wrinkle Defense Serum

If forehead lines are your concern, this serum is designed to visibly smooth fine lines and wrinkles across the face and neck, and it’s the one U Beauty calls “Your Lifelong Wrinkle Regimen.” It combines the two routes this guide compares. Its Multi-Peptide Complex sits alongside Copper Peptides, and the ingredient list names Acetyl Hexapeptide-8, Palmitoyl Tripeptide-5, and Copper Tripeptide-1. It also carries two Retinol Esters, Retinyl Linoleate and Retinyl Palmitate, plus Squalane, Vegan Silk Protein, and Centella Exosomes, all powered by proprietary SIREN Capsule Technology™. That gives you one step for the look of expression lines and fine lines together, allowing skin to look smoother and feel supple.

The SMOOTH Dynamic Wrinkle Defense Serum goes on as one to two pumps pressed upward over the face and neck, morning and evening, and it can be layered over the Resurfacing Compound. The texture is a whipped gel-mousse. It’s designed for the face and neck; the eye area has its own formula in The RETURN Eye Concentrate.

Best for: Anyone who wants peptides and a Retinoid in one serum for the look of forehead lines.

Key ingredients: Multi-Peptide Complex, Copper Peptides, Vegan Silk Protein, Centella Exosomes.

Price: $248 (30ml), $148 (15ml).

Worth knowing: It’s an investment next to the drugstore entries here, and the 15ml size is the lower-cost way in. Because it contains Retinol Esters, U Beauty recommends following morning use with a broad-spectrum sunscreen.

3. Biossance Squalane + Copper Peptide Rapid Plumping Serum

This water-based serum pairs Copper Peptides with Squalane and a set of hydrators, and the copper is what gives it a blue tint. The ingredient list names Copper Tripeptide-1, Tetrapeptide-30, Palmitoyl Hexapeptide-52, and Copper PCA alongside Squalane, Sodium Hyaluronate, Ectoin, and Acmella Oleracea Extract. Biossance directs it after cleansing and eye cream and before moisturizer, and suggests using it in the morning with a Retinol serum at night for anyone who wants both routes. Because it puts hydration first, it may help creases look softer by leaving skin looking plumper.

Best for: A hydrating peptide step for the look of forehead lines, paired with a separate Retinoid at night.

Key ingredients: Copper Tripeptide-1, Tetrapeptide-30, Palmitoyl Hexapeptide-52, Squalane.

Price: $69 (50ml).

Worth knowing: No Retinoid is listed, and the ingredient list carries a long run of botanical extracts. Biossance advises a small patch test before using it alongside a Retinol product.

4. Paula’s Choice CLINICAL 1% Retinol Treatment

Paula’s Choice gives this Retinol serum a lotion texture, and it also brings in peptides and a Vitamin C derivative. The ingredient list names Retinol, Tetrahexyldecyl Ascorbate, Palmitoyl Tetrapeptide-7, Palmitoyl Hexapeptide-12, and Palmitoyl Tripeptide-1, with Ceramide NG, Sodium Hyaluronate, and Licorice Root Extract. The brand directs one to two pea-sized pumps over face and neck, avoiding the eyes, starting three times a week and building toward nightly use as tolerated. That makes it a Retinol step with supporting peptides already in the bottle.

Best for: Normal to dry skin that wants a Retinol serum with peptides built in.

Key ingredients: Retinol, Tetrahexyldecyl Ascorbate, Palmitoyl Tetrapeptide-7, Ceramide NG.

Price: $65 (1 fl oz), listed on sale at $48.75 when we checked.

Worth knowing: Paula’s Choice notes some people may have a delayed reaction to 1% Retinol, so the slow build-up schedule matters. The brand points oilier skin to its thinner Retinol booster instead.

5. StriVectin Advanced Retinol Nightly Multi-Correct Serum

StriVectin’s evening Retinol serum surrounds its Retinoid with hydrating and comforting ingredients: Retinol, Ectoin, Polyglutamic Acid, Withania Somnifera (Ashwagandha) Root Extract, Squalane, Sodium Hyaluronate, Adenosine, and Bisabolol. StriVectin directs it onto a clean face before moisturizer in the evening. It fits a routine where the serum does the Retinoid work at night and a separate product handles the morning.

Best for: An evening Retinol step with extra hydrators.

Key ingredients: Retinol, Ectoin, Polyglutamic Acid, Ashwagandha Root Extract.

Price: $99 (1 oz).

Worth knowing: Parfum/Fragrance and Alpha-Isomethyl Ionone are listed in the ingredients, which fragrance-sensitive readers may want to weigh.

6. Peter Thomas Roth Retinol Fusion PM Night Serum

Peter Thomas Roth keeps this nightly Retinol serum short and silicone-based. The brand lists 1.5% Time-Released Microencapsulated Retinol, and the full ingredient list runs to 12 items, including Squalane, Tocopheryl Acetate, Ascorbyl Palmitate, and Bisabolol. You shake it well and apply it nightly to a cleansed face, and the brand suggests every other night if mild irritation or redness appears. It’s a straightforward pick for someone who wants the Retinoid route for forehead lines without a long list of extras.

Best for: A short nightly Retinol formula.

Key ingredients: Retinol, Squalane, Tocopheryl Acetate, Ascorbyl Palmitate.

Price: $65 (1.0 fl oz).

Worth knowing: No peptides are listed, and Alcohol appears at the end of the ingredient list.

7. La Roche-Posay Retinol B3 Pure Retinol Serum

Retinol and Niacinamide share this lightweight evening serum for the face and neck. Retinyl Palmitate, Sodium Hyaluronate, Glycerin, and Adenosine are also listed. La Roche-Posay directs three to four drops in the evening onto clean, dry skin before moisturizer, and suggests starting two to three times a week and building up as your skin adjusts. The brand describes it as suitable for sensitive skin, which makes it a reasonable first Retinoid for someone whose forehead lines are only starting to look set.

Best for: An evening Retinol serum with Niacinamide at a drugstore price.

Key ingredients: Retinol, Retinyl Palmitate, Niacinamide, Sodium Hyaluronate.

Price: $44.99 (30ml).

Worth knowing: La Roche-Posay lists it as a formula with fragrance, and Parfum/Fragrance appears in the ingredient list, as does Alcohol Denat.

8. Olay Retinol 24 MAX Night Smoothing Serum

Olay’s drugstore night serum combines two Retinoids with Niacinamide and a peptide. The ingredient list names Retinol, Retinyl Propionate, Niacinamide, and Palmitoyl Pentapeptide-4, along with Glycerin and Tropaeolum Majus Flower/Leaf/Stem Extract. Olay directs applying it after cleansing, nightly, followed by a moisturizer, and lists it as fragrance-free.

Best for: A drugstore budget with Retinol, Niacinamide, and a peptide together.

Key ingredients: Retinol, Retinyl Propionate, Niacinamide, Palmitoyl Pentapeptide-4.

Price: $46.65 (1.3 fl oz).

Worth knowing: It’s directed for night use only, and Olay recommends following it with a moisturizer and using SPF during the day.

9. RoC RETINOL CORREXION Line Smoothing Night Serum Capsules

Each capsule here holds a single evening dose of Retinol serum, which keeps the amount consistent from night to night. The ingredient list is short: Cyclopentasiloxane, Ethylhexyl Cocoate, Dimethiconol, Glycine Soja (Soybean) Oil, Retinol, Dimethylmethoxy Chromanol, Ceramide NP, and Phenoxyethanol. RoC directs one capsule in the evening after cleansing and eye cream, followed by a night cream, with SPF 30 or higher during the day. It’s the most affordable Retinoid on this list.

Best for: Pre-measured Retinol doses at a low price.

Key ingredients: Retinol, Ceramide NP, Glycine Soja (Soybean) Oil.

Price: $24.99 (30 capsules).

Worth knowing: It’s a water-free, silicone-based formula with no hydrators beyond Ceramide NP and Soybean Oil, and it’s directed for night use only.

How to Choose a Serum for the Look of Forehead Lines

• Choosing between peptides and a Retinoid: if your lines mostly show when you raise your brows, a peptide serum may be the gentler place to start. If they’ve started to look etched at rest, a Retinoid serum, or a formula that combines both, tends to be the stronger fit.

• Matching the formula to your skin’s tolerance: Retinoids can cause visible dryness or irritation at first, so start two or three nights a week and build up. A peptide serum is typically easier to use twice a day from the start.

• Keeping the routine easy to repeat: forehead lines ask for months of consistent use, so a serum you’ll actually apply morning and night tends to do more than a stronger one that sits on the shelf.

• Pairing the serum with daily sunscreen: sun exposure can make lines look deeper over time, and a Retinoid can make skin more sensitive to the sun, so broad-spectrum SPF 30 or higher is especially important.

Frequently Asked Questions

What is the best serum for fine lines on the forehead?

For most people, the strongest fit is a serum that combines peptides with a Retinoid, such as The SMOOTH Dynamic Wrinkle Defense Serum, or a dedicated Retinol serum like Paula’s Choice CLINICAL 1% Retinol Treatment. If you’d rather avoid a Retinoid, a peptide-led serum, such as HydroPeptide Power Serum, may help soften the look of forehead lines with twice-daily use.

What is the best peptide serum for expression lines?

Look for a serum that names its peptides in the ingredient list. HydroPeptide Power Serum lists seven peptides in one formula, Biossance Squalane + Copper Peptide Rapid Plumping Serum pairs Copper Tripeptide-1 with two more peptides and generous hydration, and The SMOOTH Dynamic Wrinkle Defense Serum pairs Acetyl Hexapeptide-8 and Copper Tripeptide-1 with Retinol Esters.

Can Acetyl Hexapeptide-8 help the look of forehead lines?

A 2025 review in the International Journal of Molecular Sciences reported that clinical studies indicate Acetyl Hexapeptide-8 may reduce the look of wrinkle depth and help skin look more elastic. The same review notes the peptide’s size makes it harder to get into skin, so results tend to depend on the finished formula and on consistent use.

Should I use a peptide serum or a Retinol serum for forehead lines?

Either can help, and they tend to work well together. Peptides are typically easy to use morning and night, while a Retinoid has the longer record for visible fine lines. A 2024 review in the International Journal of Cosmetic Science described Retinol, Retinol Esters, and Retinaldehyde as efficacious, safe, and well-tolerated cosmetic ingredients for the visible signs of photoaging.

How long does a serum take to soften the look of forehead lines?

Hydrating ingredients can make skin look plumper quickly, which may soften how lines appear. Changes in the look of fine lines from peptides or a Retinoid tend to build over weeks to months of consistent use, so give any serum at least a couple of months before deciding.

Can I use a forehead-line serum around my eyes?

Most of these are face serums, and several brands direct you to avoid the eye area. The skin around the eyes is thinner and often does better with a dedicated eye formula. In the U Beauty range, The SMOOTH Dynamic Wrinkle Defense Serum is for the face and neck, and The RETURN Eye Concentrate is designed for the eye area.

Related Reading

• The best copper peptide serums, compared

• The best fragrance-free eye creams for the look of fine lines

• The best moisturizers for sensitive skin