Perms and straightening: which to choose and how long it lasts

Perms and straightening are chemical services, usually combined with heat, that change the structure of your hair: a perm adds curl, waves or volume, while straightening makes hair smooth and sleek. Results last for months, which makes them popular with anyone who wants to spend less time styling each morning. Because these are chemical treatments, choosing the right technique for your hair's condition matters more than picking the prettiest photo.

At a glance

• Time: a perm usually takes 2–3 hours; straightening usually 3–4 hours, longer for long or thick hair.
• Results usually last: perms typically 3–6 months; straightened hair stays straight until it's cut off, with root touch-ups usually needed after a few months.
• Suits: healthy hair that hasn't been heavily bleached, and people who want low-maintenance styling.
• Think twice if: your hair is heavily bleached or lightened, dry, breaking or shedding; your scalp is broken; you have reacted to hair chemicals before; you are pregnant or breastfeeding — check with your doctor first.

Common options in Vietnamese salons

• Cold perm (uốn lạnh): rods and perm lotion without heat; curls look most defined when wet. Good for tighter curls and shorter hair.
• Digital or setting perm (uốn nóng): heated rods; softer curls that look best when dry. Popular for loose waves, curled-under ends and root volume.
• Chemical straightening (duỗi): relaxes curly or wavy hair.
• Thermal straightening / rebonding (ép tóc): straightening lotion plus a flat iron for very straight, glossy hair, sometimes with the ends turned under.
• Smoothing treatments (such as keratin): not permanent straightening; they reduce frizz and usually last a few months, fading with washing. Ask whether the product contains or releases formaldehyde when heated.

What happens at the salon

1. Consultation: the stylist checks your hair and asks about past chemical work.
2. Strand test, if your hair has been bleached or coloured, to see how it reacts.
3. Wash, for some techniques.
4. Softening lotion applied and left to process.
5. Rinse, then rods (perm) or section-by-section flat-ironing (straightening).
6. Neutraliser applied, left, then rinsed.
7. Conditioning, drying and tips on styling at home.

Before your appointment

• Tell the stylist about all bleaching, colouring, perms or straightening in roughly the last year.
• Don't plan bleach or a big lift in color on the same day as a perm or straightening; ask which should come first and how far apart.
• Bring photos of the result you want; for perms, include photos of dry hair.
• Set aside half a day and eat beforehand.

Aftercare

• Don't wash your hair for about 2–3 days, or as your salon advises.
• After straightening, avoid ties, clips or tucking hair behind your ears for the first few days to prevent kinks.
• Use a gentle shampoo and conditioner, blow-dry on medium heat and use a heat protectant.
• For perms, scrunch gently while damp and use a curl cream or mousse as advised.
• Vietnam's humidity makes hair frizz more easily; regular conditioning helps it hold its shape.

Visitor tip: if you're only in town for a short stay, check that your schedule allows two or three days without washing or swimming afterwards.

Questions to ask the salon

• Is my hair in good enough condition for this, or should I have a repair treatment first?
• Which products do you use, and will you do a strand test?
• How soon will I need a root touch-up?
• How does the price change with hair length and thickness?

FAQ

How long does a perm last?

Usually around 3–6 months, depending on the technique, your hair type and aftercare. Curls gradually loosen and drop as your hair grows.

What's the difference between rebonding and straightening?

In many Vietnamese salons the terms overlap. Generally duỗi means chemical straightening, while ép adds flat-ironing for straighter, glossier hair. Ask the salon exactly which process they'll use.

How much is a perm in Ho Chi Minh City?

Prices depend on the salon, the technique and your hair's length and thickness. See current prices at salons on Chepom Bookings: Da Nang · Hoi An · Ho Chi Minh City

Can I color my hair right after a perm?

It's usually better to leave a gap so your hair can recover. Ask your stylist about the right order and timing for your hair.

Can I get a perm or straightening while pregnant?

Check with your doctor first. If they're happy for you to go ahead, choose a well-ventilated salon and tell your stylist.

Book it

Find salons for perms and straightening, read reviews and book on Chepom Bookings: Da Nang · Hanoi · Ho Chi Minh City