Against bottles: the same 300ml bought as 130ml bottles is about ₹2,883, so the refill saves roughly ₹484.
Per week: 300ml runs one room about 37 weeks. ₹2,399 ÷ 37 ≈ ₹65 a week, against ₹78 on 130ml bottles and ₹107 on 50ml.
When it makes sense: once you own the glass, know the scent, will use 300ml inside about nine months, and can put ₹2,399 down at once. Two rooms on the same blend is the obvious case.
2. When you have bought the same scent twice. Buying 300ml of one blend is committing to roughly 37 weeks of it in a single room. Anyone can be sure of a fragrance for a fortnight; the useful test is whether you reordered it once already. If you have gone through a 130ml of Evening Calm and immediately wanted another, the refill is for you. If you are still deciding, ₹749 for a 50ml is the sensible amount to risk.
3. When you will get through 300ml inside about nine months. A 130ml bottle on six reeds runs 14–18 weeks, so it gives up roughly 8ml a week. At that rate 300ml is about 37 weeks in one room, about 18 weeks in each of two rooms, and about 12 in each of three. One room is a long commitment. Two rooms on the same blend is the point at which the refill stops being an act of faith and becomes ordinary housekeeping.
4. When ₹2,399 at once is easier than ₹1,249 three times. The refill is cheaper per millilitre and dearer on the day. ₹2,399 buys you 300ml; ₹1,249 buys 130ml now and lets you decide again in four months. If cash flow matters more to you than ₹484 spread across a year — and for a lot of households it genuinely does — buying bottles is not the wrong decision, it is simply a different one.
5. Never because you want a stronger or wider-reaching scent. A refill changes how long a bottle runs and nothing else. The same 130ml bottle holds the same closed, still room of up to about 150 sq ft on six reeds whether the liquid came from a refill or a new bottle. Volume buys weeks, not square feet. If a room is too big for one bottle, no quantity of refill will fix it.
Made in India, composed by an ISIPCA Versailles-trained perfumer — and a portion of every order supports girl-child education through Nanhi Kali.
Why the cheapest liquid in the range is still the wrong purchase for most people
The per-millilitre figures are not close. A 50ml at ₹749 is ₹14.98 a millilitre, a 130ml at ₹1,249 is ₹9.61, and a 300ml refill at ₹2,399 is ₹8.00. The reason is not that bigger containers get a discount on fragrance; it is that the glass bottle, the machined collar, the box and the six fibre reeds cost roughly the same whether there is 50ml or 130ml inside them, and a refill has none of those things. You are buying oil in a plain vessel. That is also exactly why the saving evaporates the moment you do not have a bottle to pour it into — the refill is priced as the second half of a purchase you have already made.
The second thing that undoes the arithmetic is time. Three hundred millilitres in one room is roughly 37 weeks — nine months of the same blend in the same doorway. Olfactory adaptation means you will stop noticing it within days of each refill, so you will not experience nine months of fragrance; you will experience nine months of visitors noticing it. That is fine if it is a scent you have already chosen twice. It is a poor bet on a blend you bought last month. A half-used ₹2,399 refill sitting in a cupboard is more expensive than any bottle we sell, because its cost per week of use is whatever you paid divided by the weeks you actually used, and abandoning it at the halfway mark turns ₹8.00 a millilitre into ₹16.00.
Three ways households reach the refill threshold
300ml refill₹2,399One bedroom, one scent you have reordered before, six reeds. 300ml is about 37 weeks of it. Against buying the same volume as bottles at ₹9.61 a millilitre — roughly ₹2,883 — the refill saves about ₹484. That is a little under ₹13 a week. Genuine, but slow, and it asks you to pay ₹2,399 today instead of ₹1,249. If your budget is comfortable and you are certain of the blend, take it. If either of those is shaky, buy the bottle and revisit in four months.Sizing by space — where the refill earns its ₹2,399
Find yourself in the left column. The cost is the real total for that situation, and one row here says spend nothing, because for that space nothing is right.
| Space | What it needs | How many | Cost |
|---|---|---|---|
| Two rooms running the same blend, glass already owned ★ | One 300ml — about 18 weeks in each room, ₹8.00 a millilitre, one order instead of two | One 300ml refill | ₹2,399 |
| One room, same scent reordered at least once | A 300ml is about 37 weeks of it — cheapest per week at about ₹65, but a nine-month commitment | One 300ml refill | ₹2,399 |
| Your first ever order | A 130ml — you need the glass, the collar and the reeds before liquid on its own is worth anything | One 130ml | from ₹1,249 |
| A scent you have owned for less than a month | A 50ml at ₹749 to be sure, or a second 130ml. Do not put ₹2,399 on a blend you have not lived with | One 50ml or one 130ml | from ₹749 |
| Four or more rooms on one blend | The 500ml at ₹3,499 is ₹7.00 a millilitre and about 62 weeks of liquid — the cheapest figure available | One 500ml refill | ₹3,499 |
| A corridor, a store room, or a guest room used twice a year | Nothing. Cheaper liquid poured into a room nobody occupies is still money spent on nobody | None | ₹0 |
| A note on all of the above: the 37-week and 18-week figures assume six reeds, a closed room and standard ceiling height, drawing roughly 8ml a week. Four reeds slows that and a hot, draughty room speeds it up, so treat them as planning numbers rather than promises. | |||
One room · the unitFrom ₹749Shop → 
Two rooms · better value₹1,498Shop → 
Large room · a switch₹1,899Shop →
Decanting, reeds, and the scent you are committing to
Pour into a clean, dry bottle and fit fresh reeds at the same time. A refill is the natural moment to change reeds, because clogged fibre is the commonest reason a diffuser seems to fade after a few months — the heavier fragrance molecules saturate the reed and the wick stops wicking. Reeds arrive with bottles, not with refills, so keep the unused set from your last bottle purchase rather than throwing it in with the packaging. If the old bottle still holds a little of the previous scent, rinse and dry it thoroughly before topping up, or the first fortnight will read as neither blend. Never mix a reed refill into a Sukoon — that machine takes the water-based Hotel Collection, and the two liquids are not interchangeable in either direction.
Decide where the remainder is going before you open it. Three hundred millilitres does not divide neatly into a 130ml bottle — it fills one roughly twice and leaves about 40ml over. That leftover is about five more weeks of use, and it is worth roughly ₹320 at refill rates, so it is worth having a plan for it. Decant it into a 50ml bottle you already own, or use it to top up mid-cycle rather than waiting for the bottle to run dry. Left in the refill container for a year it is not spoiled, but it is money doing nothing, and it is the quiet reason people conclude that refills did not save them as much as the arithmetic promised.
Then use the reeds to control what the refill actually costs you. Reed count is the only volume dial a reed diffuser has, and it sets consumption as directly as it sets strength. Six reeds is full strength and about 8ml a week; four is a bedroom setting and stretches the same liquid noticeably further. Running four reeds instead of six across a 300ml refill can push you from roughly 37 weeks towards 45 or more in one room, which takes the cost per week below ₹55 without spending anything. It is not free fragrance — you are asking for less scent per week — but in a bedroom that is usually the setting you wanted anyway.
What to buy
The refill sits at the end of a sequence, not the start of one. This table is the whole sequence, so you can see where you currently are on it.
| Buy | What it covers | Lasts | Price |
|---|---|---|---|
| One 50ml | A single reed diffuser — step one — finding out whether you like a blend, at ₹14.98 a millilitre | 6–8 weeks | from ₹749 |
| One 130ml | The value size — step two — the bottle you commit to, ₹9.61 a millilitre and about ₹78 a week | 14–18 weeks | from ₹1,249 |
| The duo | Day & Night duo — two rooms started at once, and the fastest way to reach the volume a refill needs | 6–8 weeks each | ₹1,498 |
| Sukoon | 500ml ultrasonic — a room past about 200 sq ft, which is a coverage problem no refill addresses | Runs when you switch it on | ₹1,899 |
| 300ml refill ★ | The running cost — step three — ₹8.00 a millilitre and about ₹65 a week, once the glass and the scent are settled | Roughly 2 × 130ml fills | ₹2,399 |
Versailles
The 300ml refill is the cheapest fragrance we sell and I still talk people out of it every week. ₹2,399 for 300ml is ₹8.00 a millilitre against ₹9.61 in a 130ml bottle — a saving of about ₹484 if you use all of it. If you use half of it, you have paid ₹16.00 a millilitre and bought yourself a cupboard ornament.
So the honest test is not arithmetic, it is commitment. Have you bought this blend twice? Do you have somewhere to pour it today? Will 300ml be gone inside nine months? Two rooms on the same scent answers all three at once, which is why that is the household I recommend it to and very few others.
And it changes nothing about coverage. A bottle filled from a refill holds exactly the same room as a bottle bought full — up to about 150 sq ft, closed and still, on six reeds. People sometimes reach for the biggest container hoping it will finally reach the far end of the living room. It will not. Bigger buys weeks, not square feet, and I would rather say that before you spend ₹2,399 than after. A portion of every order funds a girl's classroom through Nanhi Kali.
Frequently asked questions
- What a 300ml refill actually fills — roughly twice, plus 40ml.
- The real cost per week of each size — all five scents, checked.
- Two 50ml against one 130ml — weeks and rupees, side by side.
- What ₹3,000 genuinely buys — two rooms, properly.
- Brand: the SOSA founder story.
SOSA products & prices (verified August 2026): Hotel Collection water-based ultrasonic diffuser fragrance 15ml ₹299 · 100ml ₹999 · 300ml ₹1,799 · Pack of 7 (15ml, all fragrances) ₹1,799; refills 100ml from ₹999. Seven scents: The Ritz-Carlton-inspired (white tea · bergamot · cedar), Westin-inspired (white tea · aloe · cedar), 1 Hotels-inspired (cedarwood · vetiver · green leaves), The St. Regis-inspired (amber · violet · woods), Shangri-La-inspired (jasmine · green tea · white tea), Four Seasons-inspired (citrus · floral · sandalwood), W Hotels-inspired (citrus · pepper · amber). Diffusers: Boond 300ml ₹899 · Sukoon 500ml ₹1,899 · Megh 6L ₹3,499. Water-based, phthalate-free, composed to IFRA standards for home diffusion; 3–6 drops per tank. Made in India, Pune. The Hotel Collection scents are SOSA's own interpretations inspired by the world's finest hotels; all hotel names are trademarks of their respective owners and are used only to describe the scent style — SOSA is an independent Indian fragrance house, not affiliated with or endorsed by any hotel brand. Prices and availability subject to change — see the live product pages.