★ SOSA reed diffusers · refill or rebuy
An empty reed diffuser is not a finished product. It is a vessel and six reeds you have already paid for
★ ★ ★ ★ ★
★★★★★
"I worked out I was paying about ₹17 a millilitre for 50ml bottles. The 300ml refill halved it and I still use the same glass."
300ml refill ₹2,399
★★★★★
"Nobody told me the refill is oil only until this brand said it in the product title. My reeds were nine months old, so I bought a bottle instead."
Bought 50ml for the reeds
★★★★★
"Six fills of my little bottle out of one 300ml. I had been throwing away perfectly good glass for two years."
Fresh Brew · refilled
★★★★★
"The honest bit was being told not to buy the 500ml unless I was sure I still loved the scent in a year. I bought the 300ml."
Mountain Breeze refill
★★★★★
"₹2,399 felt like a lot until I saw it against six bottles at ₹849. That arithmetic sold it, not the marketing."
Refill maths
★★★★★
"I wanted a different scent so they told me to buy the bottle, not the refill, because the old reeds carry the old smell. Correct advice."
Switched to Garden Bloom
★★★★★
"I worked out I was paying about ₹17 a millilitre for 50ml bottles. The 300ml refill halved it and I still use the same glass."
300ml refill ₹2,399
★★★★★
"Nobody told me the refill is oil only until this brand said it in the product title. My reeds were nine months old, so I bought a bottle instead."
Bought 50ml for the reeds
★★★★★
"Six fills of my little bottle out of one 300ml. I had been throwing away perfectly good glass for two years."
Fresh Brew · refilled
★★★★★
"The honest bit was being told not to buy the 500ml unless I was sure I still loved the scent in a year. I bought the 300ml."
Mountain Breeze refill
★★★★★
"₹2,399 felt like a lot until I saw it against six bottles at ₹849. That arithmetic sold it, not the marketing."
Refill maths
★★★★★
"I wanted a different scent so they told me to buy the bottle, not the refill, because the old reeds carry the old smell. Correct advice."
Switched to Garden Bloom
✓ Refills are oil only — you reuse your own glass vessel and reeds ✓ 300ml ₹2,399 ≈ 8–11 months · 500ml ₹3,499 ≈ 14–18 months ✓ Reeds are not sold separately — SOSA guidance is to refresh them every few months
Founder Diaries · Reed Diffusers · Refill or Rebuy
Rebuy a bottle if: you want a different scent, or your reeds have gone dark, stiff and slow. A new 50ml from ₹749 arrives with six fresh fibre reeds — and reeds are not sold on their own.
The arithmetic: ₹2,399 ÷ 300ml is about ₹8 per ml and ₹3,499 ÷ 500ml is about ₹7 per ml, against ₹749 ÷ 50ml ≈ ₹15 and ₹849 ÷ 50ml ≈ ₹17 for a fresh bottle.
What a refill does not include: reeds, and a vessel. It is oil. If you have thrown the glass away, buy the bottle.
Evening Calm₹799 · 8.9/10Reeds are the consumable and oil is the stable part, which is the reverse of what almost everyone assumes. Fibre reeds — we use fibre rather than rattan because rattan's natural pores clog in Indian humidity — wick cleanly for months and then gradually slow as the heavier fraction of the fragrance accumulates in the channels. Our guidance is to refresh reeds every few months, and this is where the honest gap in our range sits: we do not sell replacement reeds as a separate item. A fresh set of six arrives only with a bottle. So if your reeds are visibly dark, stiff, or barely wet above the oil line after a day standing in fresh oil, the sensible purchase is a bottle rather than a refill — you are buying reeds and getting oil with them.
300ml refill · 8–11 months₹2,399Shop → 
Fresh Brew · new bottle, new reedsfrom ₹849Shop → 
Morning Freshness · 130ml₹1,249Shop →
SOSA reed diffuser range & prices (verified August 2026): alcohol-free, phthalate-free, paraben-free and IFRA-compliant compositions on a heat-stable coconut-derived (CCT) carrier, low-VOC, supplied in a refillable glass bottle with six fibre reeds; 50ml lasts 6–8 weeks and 130ml lasts 14–18 weeks. Morning Freshness (Malabar lemon · peppermint · Nilgiri eucalyptus) 50ml ₹749 · 130ml ₹1,249 · 9.0/10; Garden Bloom (British rose · night-blooming jasmine) 50ml ₹799 · 130ml ₹1,299 · 8.9/10; Evening Calm (Kashmir lavender · chamomile) 50ml ₹799 · 130ml ₹1,299 · 8.9/10; Fresh Brew (Coorg coffee · Kerala vanilla) 50ml ₹849 · 130ml ₹1,349 · 9.5/10; Mountain Breeze (Himalayan pine · sage · Indian cedar) 50ml ₹849 · 130ml ₹1,349 · 9.4/10. Reed diffuser refills are oil only — you reuse your own vessel and reeds: 300ml ₹2,399 (roughly 8–11 months) · 500ml ₹3,499 (roughly 14–18 months), about ₹7–8 per ml against ₹15–17 per ml for a 50ml bottle. Duo sets ₹1,498–₹1,598 for 2 × 50ml and ₹2,498–₹2,598 for 2 × 130ml. Strength figures are positions on SOSA’s own internal strength scale, not an industry standard. Replacement reeds are not sold as a separate SKU; SOSA guidance is to refresh reeds every few months. The reed line is separate from the water-based Hotel Collection for ultrasonic machines (15ml ₹299 · 100ml ₹999 · 300ml ₹1,799) and the two are not interchangeable. Diffusers: Boond 300ml ₹899 · Sukoon 500ml ₹1,899 · Megh 6L ₹3,499 · waterless Vaayu ₹11,999. Composed and handmade in small batches in Pune, India; tested through 45°C summer heat and 85% monsoon humidity. Free shipping above ₹499. A portion of every order supports girl-child education through Nanhi Kali. Prices subject to change — see the live product pages.
The bottle is empty, the reeds are still standing in it, and the question that arrives in my inbox at this exact moment is always framed the same way — should I just buy another one? Almost always the answer is no, and the reason is not loyalty or sustainability. It is arithmetic. When a reed diffuser finishes, the only thing that has actually been consumed is the oil. The glass is intact, the reeds may have months left in them, and you have already paid for both. What you buy next should depend on which of those three things is genuinely finished.
Quick answers — read this first
Refill if: you still love the scent and your reeds are only a few months old. The 300ml refill is ₹2,399 and runs about 8–11 months; the 500ml is ₹3,499 and runs about 14–18 months.Rebuy a bottle if: you want a different scent, or your reeds have gone dark, stiff and slow. A new 50ml from ₹749 arrives with six fresh fibre reeds — and reeds are not sold on their own.
The arithmetic: ₹2,399 ÷ 300ml is about ₹8 per ml and ₹3,499 ÷ 500ml is about ₹7 per ml, against ₹749 ÷ 50ml ≈ ₹15 and ₹849 ÷ 50ml ≈ ₹17 for a fresh bottle.
What a refill does not include: reeds, and a vessel. It is oil. If you have thrown the glass away, buy the bottle.
The short answer
Short answer: refill the vessel you already own if the scent is still right for the room and the reeds are young. Buy a new diffuser if you want to change fragrance, if the reeds are spent, or if you no longer have the bottle. The oil is the only consumable that finishes on schedule — 6–8 weeks for a 50ml, 14–18 weeks for a 130ml — and it is also the only part a refill replaces.
The mechanism, in money: a refill removes the cost of the glass, the reeds, the box and the packaging from the price of the oil. That is why the per-millilitre figure falls by roughly half. Working from our own listed prices: ₹2,399 for 300ml is about ₹8 per ml, ₹3,499 for 500ml is about ₹7 per ml, and a 50ml bottle at ₹749–₹849 works out at roughly ₹15–₹17 per ml — up to around 55% less per millilitre when you refill.
Shop: oil refills at ₹2,399 for 300ml and ₹3,499 for 500ml, in all five reed compositions. New bottles from ₹749 for 50ml and ₹1,249 for 130ml, six fibre reeds included. Free shipping above ₹499.
In this guide
Same scent, kept running
300ml oil refill · ₹2,399
Lowest cost per millilitre
500ml oil refill · ₹3,499
New scent, new reeds
50ml bottle · from ₹749
Straight answer
My reed diffuser is empty — do I buy a refill or a whole new one?
1. Check what has actually finished before you spend. The oil has finished; that is why you are here. The glass has not — it is refillable and it was designed to be. The reeds may or may not have. Lift one out: if it is pale, flexible and still wicks when you stand it back in oil, it has life left. If it is dark, stiff and slow to wet at the top, it is spent. Those three answers, in that order, decide the purchase.
2. Refill when the scent is right and the reeds are young. The 300ml refill at ₹2,399 is six fills of a 50ml vessel — 300 ÷ 50 = 6 — which at 6–8 weeks a fill is roughly 8–11 months of continuous scent. The 500ml at ₹3,499 is ten fills of a 50ml, or about 14–18 months.
3. Buy a new bottle when you want a different fragrance. Old reeds hold the old composition and will ghost through the new one for weeks. A change of scent needs fresh reeds, and fresh reeds only arrive with a bottle — we do not sell them separately. That is an honest gap in the range, not a sales tactic.
4. Do not buy a refill you cannot pour anywhere. It is oil in a bottle meant for decanting. If the vessel is broken, given away or in a bin, the refill is not the product for you this time.
5. Do not buy the 500ml on your first refill. Fourteen to eighteen months is a long commitment to a fragrance you have lived with for two months. Buy the 300ml, see whether you are still glad of it in the spring, then size up.
6. If you are refilling, the method takes two minutes. Remove the reeds, pour to the neck, return the reeds, then flip them once so both ends are coated. Gloves on, tray underneath — reed oil marks wood and stone.
Composed and handmade in small batches in Pune, and a portion of every order supports girl-child education through Nanhi Kali.
2. Refill when the scent is right and the reeds are young. The 300ml refill at ₹2,399 is six fills of a 50ml vessel — 300 ÷ 50 = 6 — which at 6–8 weeks a fill is roughly 8–11 months of continuous scent. The 500ml at ₹3,499 is ten fills of a 50ml, or about 14–18 months.
3. Buy a new bottle when you want a different fragrance. Old reeds hold the old composition and will ghost through the new one for weeks. A change of scent needs fresh reeds, and fresh reeds only arrive with a bottle — we do not sell them separately. That is an honest gap in the range, not a sales tactic.
4. Do not buy a refill you cannot pour anywhere. It is oil in a bottle meant for decanting. If the vessel is broken, given away or in a bin, the refill is not the product for you this time.
5. Do not buy the 500ml on your first refill. Fourteen to eighteen months is a long commitment to a fragrance you have lived with for two months. Buy the 300ml, see whether you are still glad of it in the spring, then size up.
6. If you are refilling, the method takes two minutes. Remove the reeds, pour to the neck, return the reeds, then flip them once so both ends are coated. Gloves on, tray underneath — reed oil marks wood and stone.
Composed and handmade in small batches in Pune, and a portion of every order supports girl-child education through Nanhi Kali.
TL;DR: the vessel is the asset. Refill it at about ₹8 per ml (₹2,399 ÷ 300ml) or ₹7 per ml (₹3,499 ÷ 500ml) if you still love the scent and the reeds are young. Buy a fresh bottle from ₹749 if you want to change fragrance or the reeds are spent — because the refill is oil only and reeds are not sold separately.
What you buy when nothing but the oil is finished
SOSA reed diffuser refill · oil only ₹2,399 / 300ml
The same composition that was in your bottle, in a decanting bottle with no glass vessel and no reeds — which is exactly why it costs what it costs. ₹2,399 for 300ml works out at roughly ₹8 per millilitre against about ₹15–₹17 for a 50ml bottle, and keeps a vessel running for something like 8–11 months. The 500ml at ₹3,499 is nearer ₹7 per millilitre and 14–18 months. Available in all five reed compositions, alcohol-free and phthalate-free on the same heat-stable CCT base.
Part one — three components, and only one of them finished
A reed diffuser looks like one object and behaves like three. There is a glass vessel with a narrow neck, which does nothing chemically and never wears out. There are six fibre reeds, which are the working part and degrade slowly. And there is the oil, which is the only thing you consume. When the bottle empties, the industry's instinct is to sell you all three again. That is fine for the seller and wasteful for you, and it is the reason a refill line exists at all. Below, each component and how to judge whether it is genuinely finished — because the answer to your question is simply the sum of those three judgements.
1
COMPONENT ONE · NEVER FINISHES
The glass vessel — the part you should stop rebuying
Our reed bottles are refillable by design: a heavy base, a neck narrow enough to slow evaporation from the surface of the oil, and no liner or valve to fail. Nothing in it degrades. Every time you buy a whole new diffuser because the old one emptied, you are paying again for a piece of glass that was perfectly good. Across a couple of years that is not a trivial sum — six fills of a 50ml vessel bought as six bottles of Fresh Brew is 6 × ₹849 = ₹5,094, against ₹2,399 for the 300ml of oil that fills it six times over. Wash it, keep it, stand it on a tray. The only reason to replace a vessel is breakage.
The rule: the vessel is an asset you already own. Treat rebuying it as a decision, not a default.
2
COMPONENT TWO · FINISHES SLOWLY
The six fibre reeds — the part that decides your answer
Evening Calm₹799 · 8.9/10Reeds are the consumable and oil is the stable part, which is the reverse of what almost everyone assumes. Fibre reeds — we use fibre rather than rattan because rattan's natural pores clog in Indian humidity — wick cleanly for months and then gradually slow as the heavier fraction of the fragrance accumulates in the channels. Our guidance is to refresh reeds every few months, and this is where the honest gap in our range sits: we do not sell replacement reeds as a separate item. A fresh set of six arrives only with a bottle. So if your reeds are visibly dark, stiff, or barely wet above the oil line after a day standing in fresh oil, the sensible purchase is a bottle rather than a refill — you are buying reeds and getting oil with them.
The test: lift one reed out. Pale and flexible, wet well above the oil line — refill. Dark, rigid, dry an inch up — buy the bottle.
3
COMPONENT THREE · THE ONLY TRUE CONSUMABLE
The oil — and how fast it is supposed to go
A 50ml bottle at six reeds runs 6–8 weeks; a 130ml runs 14–18 weeks. If yours emptied inside those windows it did exactly what it was built to do, and there is nothing to diagnose. If it emptied much faster, look for a draught or direct sun before you look for a fault — an AC vent blowing across the reeds strips them and empties the bottle weeks early while leaving the room smelling of very little. An empty bottle on schedule is a product that worked, not one that failed. The refill exists precisely because that schedule repeats: five or six times a year on a 50ml, three or four on a 130ml, and paying full bottle price each time is the expensive way to do it.
Part two — the arithmetic, laid out on the listed prices
Everything below is division on our own published prices, shown as division so you can check it. The per-millilitre figures are the honest way to compare a ₹749 bottle against a ₹3,499 refill, because the sticker prices are not comparable at all — one is fifty millilitres of oil with hardware, the other is half a litre of oil without.
Refill against rebuy
Every format, priced per millilitre
| What you buy | Comes with | Price | Cost per ml (arithmetic) | How long it runs |
|---|---|---|---|---|
| 500ml oil refill ★ | Oil only — no vessel, no reeds | ₹3,499 | ₹3,499 ÷ 500 ≈ ₹7 | About 14–18 months |
| 300ml oil refill | Oil only — no vessel, no reeds | ₹2,399 | ₹2,399 ÷ 300 ≈ ₹8 | About 8–11 months |
| 130ml bottle · Morning Freshness | Glass vessel and six fibre reeds | ₹1,249 | ₹1,249 ÷ 130 ≈ ₹10 | 14–18 weeks |
| 50ml bottle · Morning Freshness | Glass vessel and six fibre reeds | ₹749 | ₹749 ÷ 50 ≈ ₹15 | 6–8 weeks |
| 50ml bottle · Fresh Brew | Glass vessel and six fibre reeds | ₹849 | ₹849 ÷ 50 ≈ ₹17 | 6–8 weeks |
| The honest caveat: the refill columns look unbeatable because they exclude hardware you have to already own. A refill contains no glass and no reeds, and reeds are not sold separately — so a household that has thrown its bottle away, or whose reeds are eight months old, is comparing the wrong two rows. For those homes the ₹749–₹849 bottle is the correct buy even though its per-millilitre figure is twice as high. | ||||
Shop this guide
The three purchases this decision comes down to
300ml refill · 8–11 months₹2,399Shop → Fresh Brew · new bottle, new reedsfrom ₹849Shop → Morning Freshness · 130ml₹1,249Shop →
The SOSA principle
You bought a vessel once. After that you are only ever buying oil and reeds.
Which of those two you need is the entire question. Oil finishes on a schedule you can predict; reeds finish slowly and quietly, and only a bottle brings new ones.
Part three — the four cases, and the one where I tell you to rebuy
Case one, and the commonest: you love the scent, the room is right, and you have had the bottle two or three months. Refill. Your reeds are nowhere near spent, the vessel is fine, and the only thing missing is oil. Take the 300ml rather than the 500ml the first time — ₹2,399 against ₹3,499 — because eight to eleven months is already a long way to see ahead, and a fragrance you have loved for two months is not yet a fragrance you have loved through a monsoon and a winter. If you are still reaching for it next August, size up then.
Case two: the scent is right but the reeds are tired. This is where people go wrong most expensively in both directions. Some buy the refill, pour it over reeds that have been standing since last year, and conclude the oil is weaker than it used to be; it is not, the reeds are. Others throw out a perfectly good vessel. The correct move is slightly awkward and I would rather say it plainly: buy a fresh 50ml bottle of the same scent for the reeds it contains, run that bottle down, and buy the refill next time with reeds that are new. We do not sell replacement reeds on their own, which makes this the only route, and I am not going to pretend that is elegant.
Case three: you want a different fragrance. Buy a bottle. A refill poured into a vessel whose reeds carry the old composition will smell of both for weeks, and Fresh Brew ghosting under Morning Freshness is not a fragrance anyone designed. Case four, the one nobody expects: the bottle emptied far too fast — say a 50ml gone in three weeks. Do not buy anything yet. Find the draught. An AC vent, a ceiling fan on high, an open window in April or a patch of direct sun will pull a bottle down weeks early, and buying more oil to feed the same draught is the most straightforwardly wasted money in this category. Move the bottle first, then decide.
An empty diffuser is not a dead product. It is a vessel, six reeds and a decision about which of them is actually finished.
— Sonal Sahani, SOSA
Part four — what to buy, by situation
The whole page compressed into a table you can match yourself against in ten seconds. Prices are the current listed ones; the arithmetic in the last column is division on those prices, shown so you can check it.
The repurchase edit
Match your situation to the correct buy
| Your situation | Buy | Why | Price and what it works out at |
|---|---|---|---|
| Love the scent · reeds under three months old ★ | 300ml refill | Only the oil has finished; reeds and vessel are good | ₹2,399 · six fills of a 50ml (300 ÷ 50 = 6) |
| Love the scent · second or third refill · settled household | 500ml refill | Lowest per-millilitre price we offer, over 14–18 months | ₹3,499 · ₹3,499 ÷ 500 ≈ ₹7 per ml |
| Reeds dark, stiff and slow to wet | New 50ml bottle, same scent | Reeds are not sold separately — a bottle is the only source of six fresh ones | From ₹749 · six new fibre reeds included |
| Want a different fragrance | New bottle in the new scent | Old reeds ghost the old composition through the new one | ₹749–₹849 for 50ml · ₹1,249–₹1,349 for 130ml |
| Vessel broken or given away | New bottle, any size | A refill is oil with nowhere to go without a vessel | From ₹749 · free shipping above ₹499 |
| Two rooms to keep scented | A duo set, then refill both | Two vessels to refill later beats one bottle bought twice | ₹1,548 for 2 × 50ml · ₹2,548 for 2 × 130ml |
| Bottle emptied in three weeks | Nothing yet | Find the draught or the sunlight first; more oil feeds the same problem | Free |
Honest notes for buyers: the per-millilitre figures on this page are our own arithmetic on listed prices — ₹2,399 ÷ 300ml, ₹3,499 ÷ 500ml, ₹749 ÷ 50ml and ₹849 ÷ 50ml — not a laboratory measurement, and the duration ranges are working guidance that moves with room volume, heat, ventilation and reed count. Refills are oil only: no glass vessel, no reeds. Reeds are not sold as a separate item, and our guidance is to refresh them every few months, which in practice means occasionally buying a bottle rather than a refill. Reed oil never goes into a Sukoon or Boond, and the water-based Hotel Collection never goes into a reed bottle. Flip with gloves, stand the bottle on a tray because the oil marks wood and stone, keep it out of direct sunlight and away from children and pets. Composed and handmade in small batches in Pune, and a portion of every order supports girl-child education through Nanhi Kali.
When the reeds are what finished
SOSA Mountain Breeze · pine, sage & Indian cedar ₹849 / 50ml
If the wet-line test says your reeds are spent, a bottle is the buy — and the six fibre reeds inside it are the reason, not the oil. Fibre rather than rattan because rattan's pores clog through an 85% monsoon; tested through 45°C heat on a phthalate-free CCT base. 9.4 out of 10 on our own internal strength scale at six reeds, which is a position on our scale rather than an industry standard or a concentration. 130ml ₹1,349 for 14–18 weeks, and both sizes are refillable afterwards.
SS
ISIPCA
Versailles
Versailles
A note from Sonal
The commercially clever thing would be to say nothing and let every empty bottle become a new bottle. Home fragrance is a repeat-purchase business and the repeat purchase is where the money is. The reason we sell a refill at roughly half the per-millilitre price of the bottle is that I found the alternative embarrassing — a cupboard of identical glass vessels, each one bought because the oil in the last one ran out.
What I will not do is dress the refill up as a complete product. It is oil. It arrives with no reeds, because we do not currently sell reeds, and I would rather write that sentence three times on a page than have someone open a ₹2,399 parcel expecting six fibre sticks. We are working on it. Until then the honest instruction is the slightly clumsy one: refill twice, buy a bottle for the reeds, refill twice more.
And if the answer for your home this month is a whole new bottle in a whole new scent, that is a perfectly good answer too. Keep the old vessel anyway. It will be useful the next time only the oil runs out. Everything is composed and handmade in small batches in Pune, and a part of every order funds a girl's classroom through Nanhi Kali.
Frequently asked questions
Is a reed diffuser refill cheaper than buying a new diffuser?
Per millilitre, considerably. ₹2,399 ÷ 300ml is about ₹8 and ₹3,499 ÷ 500ml is about ₹7, against roughly ₹15–₹17 for a 50ml bottle at ₹749–₹849 — up to around 55% less. The sticker price is higher because you are buying six to ten bottles' worth of oil at once, and it only works if you still have your vessel and your reeds are in good condition.
Do SOSA refills come with reeds?
No. The refill is oil only — you reuse your own glass vessel and your own reeds. Reeds are not sold as a separate item either, which is an honest gap in our range; our guidance is to refresh them every few months, and the practical route is to buy a bottle when yours are spent.
How many times can I refill the same bottle?
As many times as you like — the glass does not degrade. A 300ml refill fills a 50ml vessel six times (300 ÷ 50) or a 130ml vessel a little over twice; a 500ml fills a 50ml ten times. What limits you is the reeds, not the vessel, so plan a fresh set every few months.
Should I buy the 300ml or the 500ml refill?
The 300ml at ₹2,399 for a first refill: it runs 8–11 months, which is long enough to be sure. The 500ml at ₹3,499 is the better per-millilitre price and runs 14–18 months, and it makes sense once you know a scent has survived a summer and a monsoon in your home without you tiring of it.
My bottle emptied much faster than 6–8 weeks. Should I buy a bigger one?
Not yet. Fast emptying almost always means a draught or direct sun — an AC vent, a fan, an open window — which strips the reeds and empties the bottle while leaving the room quiet. Move the bottle into gentle passing air away from vents and out of sunlight, and see what the next fill does. A larger bottle in the same spot simply loses more oil to the same draught.
Refill or rebuy · 2027
Keep the glass. Buy what actually finished — oil, or reeds
Oil-only refills at ₹2,399 for 300ml (about 8–11 months, roughly ₹8 per ml) and ₹3,499 for 500ml (about 14–18 months, roughly ₹7 per ml), in all five compositions. New bottles from ₹749 for 50ml and ₹1,249 for 130ml with six fibre reeds included. Free shipping above ₹499, and a portion of every order supports girl-child education through Nanhi Kali.
Shop oil refills → New bottle from ₹749
Continue the read
More on refilling and repurchasing
- Should you replace the reeds every time you refill? — how to track reed age against oil.
- Can you put a different fragrance in the same bottle? — the wash, and which pairs transition cleanly.
- Should you try a new scent when you refill? and which refill if you want it stronger.
- How to make a reed diffuser last longer — before you spend on more oil.
- Brand: the SOSA founder story.
Editorial standards & sources
About this guide: Written by Sonal Sahani, ISIPCA Versailles-trained founder and perfumer at SOSA Home & Body, on when an empty reed diffuser calls for an oil refill and when it calls for a new bottle. Arithmetic flag: the per-millilitre and fills-per-refill figures here are simple division on SOSA's listed August 2026 prices — ₹2,399 ÷ 300ml ≈ ₹8, ₹3,499 ÷ 500ml ≈ ₹7, ₹749 ÷ 50ml ≈ ₹15, ₹849 ÷ 50ml ≈ ₹17, 300 ÷ 50 = 6 fills, 500 ÷ 50 = 10 fills, 6 × ₹849 = ₹5,094 — not independent measurements. Bottle-life ranges are SOSA's own working guidance from in-house testing and customer correspondence; real results vary with room volume, ceiling height, ventilation, reed count and season. Strength ratings are positions on SOSA's internal scale at six reeds, not an industry standard. Prices are subject to change.SOSA reed diffuser range & prices (verified August 2026): alcohol-free, phthalate-free, paraben-free and IFRA-compliant compositions on a heat-stable coconut-derived (CCT) carrier, low-VOC, supplied in a refillable glass bottle with six fibre reeds; 50ml lasts 6–8 weeks and 130ml lasts 14–18 weeks. Morning Freshness (Malabar lemon · peppermint · Nilgiri eucalyptus) 50ml ₹749 · 130ml ₹1,249 · 9.0/10; Garden Bloom (British rose · night-blooming jasmine) 50ml ₹799 · 130ml ₹1,299 · 8.9/10; Evening Calm (Kashmir lavender · chamomile) 50ml ₹799 · 130ml ₹1,299 · 8.9/10; Fresh Brew (Coorg coffee · Kerala vanilla) 50ml ₹849 · 130ml ₹1,349 · 9.5/10; Mountain Breeze (Himalayan pine · sage · Indian cedar) 50ml ₹849 · 130ml ₹1,349 · 9.4/10. Reed diffuser refills are oil only — you reuse your own vessel and reeds: 300ml ₹2,399 (roughly 8–11 months) · 500ml ₹3,499 (roughly 14–18 months), about ₹7–8 per ml against ₹15–17 per ml for a 50ml bottle. Duo sets ₹1,498–₹1,598 for 2 × 50ml and ₹2,498–₹2,598 for 2 × 130ml. Strength figures are positions on SOSA’s own internal strength scale, not an industry standard. Replacement reeds are not sold as a separate SKU; SOSA guidance is to refresh reeds every few months. The reed line is separate from the water-based Hotel Collection for ultrasonic machines (15ml ₹299 · 100ml ₹999 · 300ml ₹1,799) and the two are not interchangeable. Diffusers: Boond 300ml ₹899 · Sukoon 500ml ₹1,899 · Megh 6L ₹3,499 · waterless Vaayu ₹11,999. Composed and handmade in small batches in Pune, India; tested through 45°C summer heat and 85% monsoon humidity. Free shipping above ₹499. A portion of every order supports girl-child education through Nanhi Kali. Prices subject to change — see the live product pages.