Which Size Reed Diffuser Refill Should I Buy: 100 ml, 200 ml, 500 ml or 1 L?

Match the refill to your vessel, then to how many diffusers you keep. How long 100 ml, 200 ml, 500 ml and 1 L refills last, and the mistakes that make a refill smell weak.

Short answer: Match the refill to your vessel first, then to how many diffusers you keep. A 100 ml refill fills a travel-size (100 ml) diffuser, 200 ml refills a standard full-size diffuser in one pour, and 500 ml or 1 L are for homes with several diffusers in the same scent, or anyone who wants months of one scent on the shelf. Every Velour and Vellum Reed Diffuser Refill, blended by hand in Toronto, comes in all four sizes, and if your reeds are tired too, the Refresh Kit pairs a 200 ml refill with ten fresh black fibre reeds.

Start with the vessel, not the bottle

The right refill size is mostly decided before you shop, by the bottle already on your shelf.

Check the volume. Most reed diffuser vessels are 100 ml or 200 ml, and many are marked on the base or the original box.
If you are not sure, measure it. Fill the empty vessel with water from a measuring jug to the level the fragrance used to sit at, note the amount, then empty it and dry it completely before you pour any fragrance in. Water left inside will cloud the refill.
Leave room for the reeds. Fill to where the original fragrance sat, not to the brim. Reeds take up space, and an overfilled neck is how spills happen.

Velour and Vellum refills pour into our own vessels or any standard reed diffuser bottle. Our 200 ml diffusers take a 200 ml refill in one pour, and our 100 ml travel diffusers take a 100 ml refill.

How long each size lasts

Our planning rule for refills is about 60 days per 100 ml in an average room. Real rooms vary: more reeds, warm dry air, a sunny windowsill or a spot near a heating vent all use liquid faster. Our own full-size 200 ml diffusers are rated at 60 to 90 days, and our 100 ml travel diffusers at 45 to 60 days.

Refill size	What it does	Rough guide
100 ml	Refills one travel-size diffuser, or tops up a full-size one	About 2 months in one diffuser
200 ml	Refills one full-size diffuser in a single pour	2 to 4 months, depending on room and reeds
500 ml	Two full-size refills plus a top-up, or five travel-size refills	Several months of one scent
1 L	Five full-size refills, or ten travel-size refills	Many months; plan by the number of refills

For a closer look at what slows or speeds a diffuser, see how long does a reed diffuser last.

Which size suits your home

One travel diffuser on a desk or in a powder room: 100 ml.
One full-size diffuser in a living room or entry: 200 ml. If the reeds have already seen a refill or two, choose the Refresh Kit instead, since it includes ten new reeds.
Two or three diffusers in the same scent: 500 ml. One bottle refills them all in turn, and every room stays consistent.
A whole home in one signature scent, a rental, or a front desk that is never without a diffuser: 1 L.
Still deciding on a scent: 100 ml, or a travel reed diffuser, which you can later top up with any of our refills. The Sanctuary Mystery Box is another way in: three different refills, 30 ml or 100 ml each, chosen by our atelier.

Don't forget the reeds

Fresh liquid on old reeds is the most common reason a refilled diffuser smells weaker than the first time. Reeds slowly fill with dust and spent fragrance, and they stop drawing evenly.

Change the reeds with every refill. Fibre Reed Sticks come in packs of 10, 25 and 50 and fit standard-neck bottles.
Flip them once a week. It refreshes the throw without using up the refill too quickly.
Use fewer reeds in small rooms. More reeds mean more scent, but a faster-emptying bottle. Our guide to what size reed diffuser you need has a simple reed count for each room.

Storing a larger bottle

If you buy 500 ml or 1 L, you will be pouring from it for a while. Our refills are sealed in amber glass, which protects the scent from light. Store the bottle upright, tightly capped and out of direct sun, and pour only what you need for each refill. For more on how long fragrance keeps once opened, see fragrance oil shelf life and storage.

Mistakes to avoid

Buying a litre of a scent you have not lived with. Start with 100 ml or a travel diffuser. Scale up once it has held your interest for a few weeks.
Pouring a refill into a scent machine. Reed Diffuser Refills are for reed diffusers only. Never pour one into a Scaldera or any cold-air (nebulizing) or HVAC diffuser; those take Cold-Air Concentrate. See Cold-Air Concentrate or Reed Diffuser Refill.
Putting a concentrate straight on reeds. A Cold-Air Concentrate needs our Reed Diffuser Base first: 3 parts base to 1 part oil, rested 24 hours before the reeds go in.
Topping up one scent with another. Let the old scent finish, or empty and rinse the vessel first. Our guide to cleaning and reusing a reed diffuser bottle shows how.
Expecting more liquid to mean more scent. A fuller bottle lasts longer; it does not smell stronger. Strength comes from the number of reeds, fresh reeds and placement.

Quick picks

Top up a travel reed diffuser: Reed Diffuser Refill — Thé Blanc, 100 ml
Refill a full-size diffuser and start with fresh reeds: Refresh Kit
Keep two or three rooms in one scent: Reed Diffuser Refill — Santal Vellum, 500 ml
Stock a whole home or a front desk: Reed Diffuser Refill — Grand Foyer, 1 L
Try three new scents without committing: Sanctuary Mystery Box
Replace tired reeds: Fibre Reed Sticks
Starting from an empty shelf: Diffuser Vessel — Blacked-Out, 200ml with a 200 ml refill

All fourteen of our reed diffuser refill scents, from Thé Blanc to Oud Nº1, come in 100 ml, 200 ml, 500 ml and 1 L.

Frequently asked questions

What size reed diffuser refill do I need? Match it to your vessel: 100 ml for a travel-size diffuser, 200 ml for a standard full-size diffuser. Choose 500 ml or 1 L if you keep several diffusers in the same scent or want several refills on hand.

How long does a 200 ml reed diffuser refill last? Plan on about 60 days per 100 ml in an average room, so roughly two to four months for 200 ml. More reeds, warm dry air and sunny spots use it faster.

Will a Velour and Vellum refill fit a reed diffuser bottle from somewhere else? Yes. Our refills are ready to pour into any standard reed diffuser bottle. Add fresh reeds when you refill.

Is a 1 L reed diffuser refill worth buying? It makes sense if you already know the scent and keep several diffusers, since it covers about five full-size refills. If you are still choosing a scent, start with 100 ml.

Can I put a reed diffuser refill in my scent machine? No. Reed diffuser refills are for reed diffusers only. A cold-air (nebulizing) or HVAC diffuser needs a Cold-Air Concentrate.

Velour and Vellum reed diffuser refills are blended by hand in Toronto, IFRA-compliant and made without phthalates, parabens or formaldehyde. They ship across Canada and the US.

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