Henna on hair is permanent. It does not wash out. What people mean by how long it lasts is how long it looks fresh, and that is roughly four to six weeks before regrowth and fading become obvious. Henna mixed with indigo for brown or black fades faster, often two to four weeks.
How long does henna last on hair? Two different questions
Henna binds to the protein in the hair shaft and stays there. Shampoo will not lift it. The dyed length stays dyed until it is cut off.
So the strand itself keeps its colour more or less indefinitely. What changes is everything around it. New growth comes in at the root with no colour on it. The oldest ends have been through the most washing and sun and look duller than the mid-lengths. The overall effect drifts out of alignment even though nothing actually washed out.
For most people that drift becomes visible somewhere between week four and week six. Hair grows about a centimetre and a quarter a month, so by six weeks there is a clear band at the root.
Why the indigo shades fade sooner
If you use henna alone for red, the colour is very stable. Reds hold for months and often deepen over the first few days.
Brown and black are henna with indigo layered over it, and the indigo half is the weaker link. It sits less firmly than the henna underneath. As it wears, the red beneath starts to show through, so a black fades toward dark brown and a brown warms up and goes reddish at the ends. That usually starts around week two or three.
This is why people running dark shades refresh more often than people running red, and why a black line needs a maintenance routine built into how it is sold.
What speeds fading up
| Factor | Effect |
|---|---|
| Sulfate shampoos | The biggest one. Strong detergents strip indigo quickly |
| Hard water | Minerals dull the colour and speed up fading |
| Washing frequency | Daily washing fades dark shades in weeks |
| Sun and chlorine | Both lift and dull colour, particularly on the ends |
| Heat styling | Regular high heat shortens how long a shade looks fresh |
Washing every second or third day with a mild sulfate-free shampoo is the single change that makes the most difference. Customers who do that commonly get an extra two or three weeks out of a dark shade.
The first 48 hours matter most
Colour is not finished when you rinse. Henna keeps developing for a day or two as it oxidises, and the indigo step darkens noticeably over the same window.
Washing with shampoo inside that first 24 to 48 hours strips colour that has not fully set, which shortens the life of the whole application. Rinse with water, leave it, and let it finish. This one instruction prevents more disappointment than anything else on the pack.
How material quality changes the answer
Two lots of henna can behave completely differently, and longevity is where it shows.
Dye strength. Henna loses strength in storage. Old stock deposits less colour, so there is less there to begin with and it fades sooner. Crop year is a fair question to ask any supplier.
Milling. Finely sifted powder makes a smoother paste that coats the strand evenly. Coarse material sits unevenly, so parts of the head fade before others and the result looks patchy rather than softened.
Storage. Heat and light degrade it. Sealed, cool and dark keeps a lot usable far longer than a warehouse in summer.
Refreshing without going too dark
Henna builds. Every application adds another layer, so a full head reapplication every six weeks gradually goes darker and heavier than intended, especially on the ends.
The usual approach is to henna only the regrowth at the root, then pull the mix through the lengths for the last ten minutes if they need reviving. For brown and black, refreshing just the indigo step is often enough, since that is the half that has actually faded.
Sourcing henna and indigo in bulk
We mill henna powder and indigo powder ourselves at Sojat in Rajasthan, the district most of the world’s cosmetic grade henna comes from. Because both are our own lines, crop year and dye strength are things we can hold consistent from lot to lot rather than take on trust from a trader.
Minimum order is 50 kg on each, with a Certificate of Analysis on every lot and PPD tested and absent. Free sample before you order and a quote within 24 hours to your port. We supply brands in over 60 countries, including several running dark shade lines where fade performance is the thing customers judge them on.
Specifications, for buyers who order to a number
Dye strength and sieve size are the two figures that predict how a henna lot performs and how long the result holds. Both are confirmed on the Certificate of Analysis for the lot you actually receive. Tell us what your formulation is written against and we will confirm what we can supply before you order.
Frequently asked questions
Does henna wash out of hair?
No. It binds to hair protein and is permanent. It fades and grows out, but shampoo will not lift it and the dyed length stays dyed until it is cut.
How long does henna and indigo black last?
Usually two to four weeks before the black starts warming toward brown, because the indigo layer wears sooner than the henna underneath. Mild sulfate-free shampoo and less frequent washing extend that noticeably.
Why did my henna fade so fast?
The most common causes are washing with shampoo inside the first 48 hours, sulfate shampoo afterwards, hard water, or henna that had lost dye strength in storage. The first two are the easiest to fix.
Should I reapply henna to all my hair each time?
Better not to. Henna builds with every application and full-length reapplication goes darker and heavier over time. Do the regrowth, and pull the mix through the ends only for the last few minutes if they need it.
What is the minimum order for bulk henna?
50 kg, and 50 kg on indigo. Send your grade, sieve and destination and we will quote within 24 hours with a free sample first.
Specs change with the crop, the season and the grade. Ask our export desk for a current lab report, the minimum order and a price to your port, and we will come back within 24 hours.