This article was updated in April to reflect the latest prices and deals.
No matter how much conditioner or nourishing oil we apply to our hair, that longed-for silky softness can be all too fleeting.
Locking in hydration will help keep hair healthy, but if you’re dealing with existing damage and looking for lasting strength and shine, you’ll need a product that penetrates deep within the hair shaft to re-build integral bonds.
So, if you're coveting that Claudia Winkleman gloss but seem permanently stuck with frazzled lengths, it may be worth trying one of our best hair repair treatments, expert-tested by the Good Housekeeping Institute.
Here are our top-rated formulas at a glance, but keep scrolling for everything you need to know about these hair treatments and for our full reviews.
The best hair repair treatments for 2024
1
Best hair repair treatment
K18 Leave-in Molecular Repair Hair Mask 15ml
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2
Joint runner-up and best for fast results
Philip Kingsley Bond Builder Split End Remedy
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3
Joint runner up and best bond-building treatment in lab
Wella Professionals Ultimate Repair Miracle Hair Rescue Spray 95ml
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4
5
Best for dull hair
Bumble and Bumble Bond-Building Repair Hair Treatment
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6
7
Best for curly hair
Umberto Giannini Curl Oil Bond Repair
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8
Best for ease of use
Sebastian Professional No.Breaker Leave-in Spray 100ml
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9
Best bond-building shampoo
Redken Acidic Bonding Concentrate Shampoo 300ml
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It was a decade ago when Olaplex first put bond-building hair treatments on the map — now you’ll find a structure-fortifying, damage-repairing formulation in almost every haircare range.
Nicole Petty, hair expert at Milk + Blush, has noticed a dramatic rise in the popularity of hair bond builders in recent years. “Designed to chemically repair strands damaged by bleach, heat and styling, they’re a step up from regular hair masks and products that only improve the hair’s surface,” she explains.
While Olaplex uses a patented active ingredient to repair disulphide bonds inside the hair, other brands are now harnessing equally powerful molecules that penetrate further within the hair shaft to repair stressed strands, making them more resilient to damage.
Each treatment uses different technologies, but the goal is always the same — stronger, shinier and altogether healthier-looking hair that’s more manageable and less prone to breakage. Some products also focus on fortifying “virgin” strands that haven't been heat or colour-damaged, making them a smart buy for everybody.
How do hair repair treatments work?
“Bond builders repair the protein bonds that make up the keratin structure of your hair,” Petty tells us.
“They target three specific chemical bonds: disulphide (responsible for stabilising protein chains and bolstering the strength of individual hair strands); hydrogen bonds (which maintain resistance to elements such as heat and water and give your hair its texture and shape); and salt bonds (which can be prone to breakage if the hair’s pH becomes too acidic or alkaline.)
“You can repair the disulphide bonds by using a weekly bond repair treatment, or using a split end sealer to ensure already damaged ends are temporarily sealed, preventing them from splitting further up the hair shaft and reducing further breakage,” says Petty.
“The main benefit of bond-building products is that they repair broken links in the hair’s cortex, providing increased strength and resilience to damage — from heat styling and colouring — which can help to reduce split ends, breakage, dryness, tangles and frizz.”
Who needs hair repair treatments?
“Bond-building treatments were previously only available in professional salons at an additional cost,” explains Petty. “However, with the ongoing cost of living crisis reducing disposable income, salon visits and professional treatments have become less popular in lieu of more affordable home treatment alternatives.
“You can use these products on any hair type, but they’re targeted at repairing damaged hair,” she adds. “When it comes to thicker hair, usually you would need to use more of the product than is suggested to ensure the ends are fully covered and it can work most effectively.”
But which treatments are actually worth the investment? Read on for the GHI Approved bond-builders that brought damaged hair back to life for our panel and in the lab.
How we test hair repair treatments
The GHI recruited over 200 panel members to test 12 brands of bond-building treatments for eight weeks, before asking them to report back on the product's ease of use and any improvements in hair strength, frizz, tangles and shine.
Our experts then used a Dia-Stron machine to assess damage repair on bleached hair after each treatment.
1
Best hair repair treatment
K18 Leave-in Molecular Repair Hair Mask 15ml
Score: 86/100
Taking the crown is this leave-in formula, which left our panellists’ hair stronger, shinier and smoother thanks to a patented bioactive peptide, claimed by the brand to be the “miracle molecule”.
Our testers were particularly impressed by how it reduced frizz and left their hair sleeker and more manageable, without adding grease. It was also found to be “extremely effective” at preventing and repairing damage by our lab team.
Key specifications
| Hair repair technology | K18Peptide™ |
|---|
2
Joint runner-up and best for fast results
Philip Kingsley Bond Builder Split End Remedy
Score: 85/100
Tapping into the new wave of plant-based peptides helping to reverse hair damage, this formulation uses hydrolysed oat protein to soften and hydrate lacklustre locks.
Our lab test found it strengthened strands instantly, while our testers also noticed an immediate improvement in how healthy their hair looked. The sweet scent proved divisive, but all agreed this treatment ramped up softness, smoothness and shine.
Key specifications
| Hair repair technology | Plant-based peptides |
|---|
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3
Joint runner up and best bond-building treatment in lab
Wella Professionals Ultimate Repair Miracle Hair Rescue Spray 95ml
Score: 85/100
AHAs and omega-9s are the power duo in this formulation, tasked with the challenge of fighting unwanted frizz and rebuilding bonds inside the strands. Claiming to make hair 12 times softer, did this spray's results match its smooth-talking abilities?
Testers said hair felt thick and healthy “like they'd had had a fresh cut” after the trial period, with some praising the “zingy” fragrance, too. This one scored 5/5 on the Dia-Stron machine, which measures a product's ability to stem frizz and flyaways, and most of our panel agreed their hair was more manageable after use.
The only minor complaints were about the bottle not being big enough (our panel clearly couldn’t get enough) and the lovely scent fading before testers would have liked. But we don't think they're deal-breakers.
Key specifications
| Hair repair technology | Omega 9 fatty acids |
|---|
4
Best for coloured hair
Living Proof Triple Bond Complex
Score 82/100
Claiming to make hair eight times stronger against breakage than untreated lengths, this product had a lot to prove. But, it didn't disappoint. Building three types of bonds — hydrogen, ionic and covalent — with one formulation, it was proven to help make bleached hair more resilient in our lab tests.
Testers with colour-treated hair also enjoyed a boost in vibrancy and hydration after use, making it a top pick if you regularly reach for the dye.
Key specifications
| Hair repair technology | Builds hydrogen, ionic and covalent bonds |
|---|
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5
Best for dull hair
Bumble and Bumble Bond-Building Repair Hair Treatment
Score: 82/100
From the golden packaging to the product inside, this formulation delivered on glossiness. It’s powered by a strengthening complex derived from honey — a nourishing ingredient that also locks in moisture — leaving dull lengths smooth, sleek and shiny.
Testers praised the fresh scent, saying their hair smelt clean for hours after use, and many noticed fewer split ends and flyaways.
Key specifications
| Hair repair technology | Honey-derived complex |
|---|
6
Best for smoothing
Aveda Botanical Repair Leave-In Treatment
Score: 80/100
Moisturising, softening and strengthening with the help of plant-powered molecules, this treatment works to reinforce the hair’s internal structure by building thousands of new hydrogen bonds.
Our lab team found it adept at tackling damage, and our panel noticed a lasting reduction in unwanted frizz and flyaways — especially those with curly texture, who found their hair much easier to manage. The "forest-y" fragrance was a particular hit, with testers saying the scent lingered even after styling.
Key specifications
| Hair repair technology | Plant-powered molecules |
|---|
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Score: 80/100
Designed with curly and coily hair in mind, Umberto Giannini products often come out top for textured hair in our tests. This time, the bond-building treatment was very effective at reducing damage and repairing bleached tresses, with testers reporting “defined and bouncy” hair that felt and looked healthier.
There were some grumbles about the bottle size among those with big, ringleted hair — although it’s affordable as a single unit, you may need to buy two to do the job.
Key specifications
| Hair repair technology | Not disclosed |
|---|
8
Best for ease of use
Sebastian Professional No.Breaker Leave-in Spray 100ml
Score: 79/100
Our panel found incorporating this into their wash routine an easy habit to stick to, as the spray format and leave-in formula combined to create a convenient hair health-enhancer.
The results speak to the brand’s professional standards, with testers taking great pleasure in their fuller, thicker and stronger strands. Some were a little unsure about the “clinical” fragrance, but said the smell wasn’t strong enough to put them off.
Key specifications
| Hair repair technology | Apple acid and styling polymers |
|---|
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9
Best bond-building shampoo
Redken Acidic Bonding Concentrate Shampoo 300ml
Score: 77/100
Redken is mid-range household name with a focus on protecting colour, and its “find the hue for you” AI colour matching tool has taken the internet by storm. But how does its Acidic Bonding range fare when it comes to fortifying hair against breakage?
Well, our panel was impressed with how quickly this shampoo got to work, with some noting it made hair shinier and glossier after only a few washes. Testers agreed their hair felt stronger and said they experienced less breakage after regular use, but many said they would have preferred a bigger bottle.
Key specifications
| Hair repair technology | Citric acid and bonding care complex |
|---|
Tested byMaria Kumar
Beauty and Grooming Testing Manager
Maria is our Beauty and Grooming Testing Manager, and since joining in mid-2022, she has managed the testing for mutiple categories including scalp scrubs, collagen supplements and retinol serums. In addition to her master's degree in chemical engineering and a diploma in cosmetic science, she recently received her MBA from the London College of Fashion, focusing on case studies within the beauty industry. Prior to joining the company, she worked within the global technical team at the Estee Lauder Companies for over six years, collaborating with the chemists and engineers to launch luxury beauty products at scale and to quality. She has also worked as a formulation scientist within the pharmaceutical industry and takes this evidence based approach into all her product testing.
