The 13 Best Hair Growth Serums for Thicker Hair in Days (2024)

Nutrafol is one of the only hair-growth supplements that actually work, so you can trust that the brand's hair serum is worth the investment. Made with protein-rich ashwagandha exosomes, Irish moss peptides, and pea sprout extract—all of which help strengthen and hair and promote thickness—it's the ideal complement to taking the supplements.

What the reviews are saying:

"Great product. Been using it for 3 weeks now. I have noticed less hair fall in my comb. Does not leave hair greasy. I am combining with the vitamins." —Lili2022

If you get turned off by the greasy results from hair and scalp oils, consider this water-based formula. Featuring nourishing ingredients like plant peptides, niacinamide, ashwagandha, and caffeine, it helps stimulate hair growth as it supports scalp health.

What the reviews are saying:

"I've been using this daily for about two-ish weeks. While I can't comment if it's helping my hair grow, I will order another bottle to get the full effect as you typically can't see changes in 30 days. It smells great and doesn't leave my hair super oily either. I like to apply it at night so that I don't mess with my hair after application."

Dani Austin's hair care line has a devoted following, in part thanks to this scalp serum (it has over 12,000 reviews!). Containing copper tripeptide-1 for growth, tea trea oil to soothe the scalp and detox, and invigorating menthol and peppermint oil, it helps improve circulation, remove buildup, and give hair an overall thicker appearance.

What the reviews are saying:

"I had a bald spot on the top of my head, and thinning of hair all around. I started using a natural shampoo plus Divi. Man, within of one month of CONSISTENT use my hair grew back and then some!" —Jen

This overnight treatment is made with caffeine and redensyl to combat hair loss, as well as conditioning betaine. Liu recommends this inexpensive option for those with alopecia, also called androgenetic hair loss.

What the experts are saying:

“Caffeine has preliminary data to support hair growth, especially for androgenetic hair loss,” says the derm.

Rubenstein “loves” this serum from Monat containing caffeine, antioxidants, and melatonin. Plus, it has a lightweight consistency and is fragrance-free.

What the experts are saying:

“It promotes hair growth, density, scalp health, and is totally safe to use daily,” says the hairstylist.

Vegamour is renowned in the hair-growth space, and the clinical studies support it too: 52 percent of subjects saw an increase in the appearance of hair density, while 76 percent saw a reduction in hair shedding. Plus, it's pleasantly scented with bergamot essential oil

What the reviews are saying:
"I’ve only been using Gro for three months and already have amazing results! I had severe postpartum hair loss that just wasn’t returning after having my baby 18 months ago. My thinning areas haven’t filled in completely yet, but if I’ve had this much success in only 3 months I can’t wait to see it at the six month mark!"

If you hate the feeling of heavy products on your scalp, consider this lightweight, leave-in formula that feels more like a face serum. It features a five percent biomimetic peptide blend to support thinning, plus hyaluronic acid to hydrate, and green tea to soothe itchiness. Plus, it won't leave any residue on your scalp.

What the reviews are saying:

"I love how lightweight this is. It almost feels like water and has no scent. It is not greasy so I can apply it between washes on dry hair." —Emily R.

This daily treatment has a bevy of strengthening ingredients like rice water extract, biotin, and arginine to nourish the scalp and roots. It's also oil-free, and can be applied to wet or dry hair.

What the reviews are saying:

“I swear by The Inala Power Potion. My edges are back and my problem areas have new growth.” —Ebone

This collagen-infused hair serum is touted for hydrating the scalp while promoting the thicker, fuller hair – all without disrupting your current hairstyle.

What reviews are saying:

"The Hair Density Boosting Treatment is my new holy grail product. After 8 weeks of daily use, my wavy hair is noticeably fuller and sheds less. The serum is lightweight, easy to apply and leaves no greasy residue - just a pleasant fragrance. A must-have for healthier, thicker hair!" – Nikkicherie

Act + Acre, a brand built on scalp care, uses two percent Swiss apple stem in its scalp serum. Use it daily to see less thinning and more hair density in just 30 days, and to soothe the scalp.

What the reviews are saying:

"I haven’t been using this product for very long, but I am already seeing less hair in my shower drain. And my stylist has noticed how much better my hair looks."

This affordable serum is made with three percent Redensyl and two percent Capixyl (hence the name), to quickly absorb without leaving a residue. And while some hair growth products can have a clinical smell, but this highly rated serum has a fresh fragrance.

What the reviews are saying:

"I have been using this for almost a year. It does take a little time but it works. New hair growth comes in and you just need to keep at it. My thinning spot on my crown has filled in slowly." —Connie M.

A combination of watermelon seed, pumpkin seed, green tea, and more extracts make up this formula. You can leave the treatment oil on for as little as 30 minutes, or as long as 12 hours; either way, you’ll start noticing less fallout and stronger hair in 12 weeks.

What the reviews are saying:

"This product is magical. I’ve used it 2-3 times a week for six weeks and it’s greatly improving my hair." —Stella9907

Don't love an oil-based formula? This has a refreshing gel texture that absorbs easily into the scalp. In addition to rosemary oil—which has been studied for its hair-growth properties—it also features apple cider vinegar, which the real ones know is a must for a balanced scalp.

What the reviews are saying:

“Don't know if my hair is getting thicker yet, but my hair's texture is so soft and silky. And my scalp feels nice and hydrated. And the voume and bounce has returned to my hair.” –Velvet

• Jenny Liu, MD, FAAD, is board-certified dermatologist based in Minnesota.
• Clariss Rubenstein is a celebrity hairstylist who has worked with Jennifer Garner, Dakota Fanning, and Mindy Kaling.