How to Grow Hair Faster: What Actually Helps (NZ)

Updated November 2026. Prices are our live online prices.

"How do I make it grow faster?" comes up in the chair most weeks, usually from someone growing out a bob or a fringe. We'll be straight with you. The rate is mostly set by your body. The length you end up with is the part you can do something about, and that's where most people lose months without realising.

How fast does hair grow?

On average, scalp hair grows roughly a centimetre a month, so somewhere around 12 to 15cm a year. Some people are a bit quicker and some slower, and it tends to slow as we get older.

Each hair grows for a few years, then rests and falls out, and a new one starts in the same follicle. How long that growing phase lasts is largely genetic. It's why some people can grow hair to their waist and others find it stalls around the shoulders no matter what they do.

How to make your hair grow faster: what actually affects it

• Genetics and age. The biggest factors, and the ones you can't change.
• Hormones. Pregnancy, the months after a baby, and perimenopause all change how hair grows and sheds. See postpartum hair loss.
• General health. Illness, very low iron, thyroid problems, crash diets and some medications show up in your hair, often two or three months later. A GP can check these with a blood test.
• Stress. A rough patch can mean extra shedding a few months on.
• How you treat the hair you've got. This one is yours to control, and it's the rest of this page.

How to grow long hair: keep the length you grow

If your hair grows a centimetre a month but snaps off at the ends just as fast, it looks like it isn't growing at all. Most people trying to grow their hair are really fighting breakage.

1. Trim little and often. Half a centimetre to a centimetre every 10 to 12 weeks takes split ends off before they travel up the hair. Skipping trims usually means losing more later.
2. Turn the heat down. Use a heat protectant every time and medium heat on the dryer and irons. Our heat protectant guide has the ones we use.
3. Be gentle when it's wet. Detangle from the ends up with conditioner still in, using a wide-tooth comb.
4. Loosen your ponytail. Tight ties in the same spot every day snap hair and can pull at the hairline. Use soft ties and move the position.
5. Condition every wash and use a mask once a week on the mid-lengths and ends.
6. Seal the ends. A leave-in on damp ends protects the oldest, most fragile part of the hair. See how to fix dry, damaged ends.

Two ways to fix it: Sebastian NO.BREAKER or Kérastase Genesis

Both ranges are built around breakage, which is what stops most hair getting longer. Choose by budget and by where your problem is.

Sebastian NO.BREAKER is the lower price point. The shampoo and leave-in work on the lengths, and the leave-in doubles as a styling cream with heat protection up to 230°C, which suits anyone who blow-dries or straightens most days. UKIYO is Wella New Zealand's No.1 Sebastian Professional retailer, and NO.BREAKER is one of the ranges we sell most of. There's more in our NO.BREAKER guide and the NO.BREAKER collection.

Kérastase Genesis is the premium option and works differently. Kérastase make it for hair fall caused by breakage, and the Genesis Serum goes on the scalp every day. If what's bothering you is the amount of hair in the brush rather than dry, snapping ends, start here. The full range is in the Genesis collection.

A third option sits between the two. Redken Extreme Length Sealer ($44.89) is a leave-in for ends you're growing out, with biotin and castor oil in Redken's Length Care Complex. We wrote it up in growing longer hair with Extreme Length.

Hair growth serum, oil and shampoo: what they can and can't do

None of the products we stock claim to make hair grow faster, and we'd be wary of anything on a shelf that does. Here's what each type can honestly do:

• Hair growth serums are scalp leave-ins. The good ones look after the scalp and help reduce hair fall from breakage. They don't change how fast hair grows.
• Hair growth oils mostly help the lengths. Oil on the ends reduces friction and snapping, which keeps length on. Sebastian Dark Oil ($29.88) is the one most of our clients use.
• Hair growth shampoos are on your scalp for a minute or two. A strengthening shampoo helps the hair you have resist breakage, which is worth having, but that's the extent of it.

Biotin and rosemary oil: are they worth it?

Biotin supplements get recommended everywhere. Low biotin is uncommon, and if your levels are normal there's little reason to think extra will speed anything up. Talk to your GP or pharmacist before you take it, and tell them if you're due for a blood test, because biotin can affect some results.

Rosemary oil has had a lot of attention online on the back of a small amount of research. We don't sell it. If you try it, dilute it, patch test first, and stop if your scalp gets itchy or red.

What a salon routine can and can't do

It can keep more of your length on, make the ends look thicker and healthier, keep the scalp clean and comfortable, and stop you losing hair to tight styles or heat. It can't change the speed your hair grows, and it can't regrow hair that has stopped growing.

If your hair is coming out in handfuls, in patches, or your part or hairline has changed, that's a GP or dermatologist question, not a shampoo one. Read why is my hair falling out first, then make the appointment.

Growing something out? Book a cut and tell us your end goal. We'll take off only what's needed and give you a plan for each trim between now and then.

Questions we get asked

How fast does hair grow?

Roughly a centimetre a month on average, so around 12 to 15cm a year. It varies from person to person and tends to slow with age.

How can I make my hair grow faster?

You can't change the rate much. What you can do is keep the length you grow: trim little and often, use less heat, detangle gently and use a strengthening routine to cut breakage.

Do hair growth serums work?

Good scalp serums look after the scalp and can reduce hair fall from breakage. They don't make hair grow faster, and the ones we stock don't claim to.

What's the best shampoo for hair growth?

There isn't a shampoo that speeds growth. For keeping length on, we use Sebastian NO.BREAKER or Kérastase Genesis, depending on budget and whether the issue is the lengths or hair fall.

Does trimming your hair make it grow faster?

No, growth happens at the scalp. Regular small trims stop split ends travelling up the hair, so you keep more length over time.

Does biotin make hair grow?

Only if you're genuinely low in it, which is uncommon. Talk to your GP or pharmacist before taking it, especially before a blood test.

Is rosemary oil good for hair growth?

The research is limited. We don't sell it. If you try it, dilute it and patch test first, and stop if your scalp reacts.

Can you make hair grow faster in a week?

No. At about a centimetre a month, a week is a couple of millimetres whatever you use.

Everything we sell is genuine salon stock, bought direct from the brands' New Zealand distributors and shipped from our salon on Helwick Street in Wānaka. Free NZ shipping over $75.