Do Candles Expire? Shelf Life and Storage
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Candles don't expire in a safety sense — wax doesn't spoil and an old candle is not dangerous to burn. What degrades is fragrance. A scented soy candle holds its scent best for about one to two years from pouring, after which the throw gradually weakens. Stored lidded, upright, cool and out of sunlight, it will keep considerably longer than one left open on a shelf.
There's no expiry date on a candle because there's nothing to expire. But "will it still smell like anything" is a fair question, and the answer is more interesting than yes or no.
What actually changes over time
Fragrance fades
Fragrance oil is a mix of volatile compounds — that's the whole point, they evaporate so you can smell them. In a jar sitting on a shelf, the lightest of those compounds slowly leave the exposed surface of the wax, particularly with no lid on. The top notes go first, then the heart.
Base notes are the survivors. A candle built on wood, resin and musk ages far better than one built on citrus, because the heavy molecules that anchor a fragrance are also the ones that evaporate slowest. There's more on that structure in fragrance notes explained.
Practically: after a couple of years, an unlit candle's cold throw — what you smell with your nose over the jar — will be noticeably weaker. Its hot throw holds up better, because burning releases fragrance from the whole depth of the melt pool, not just the surface that's been exposed to air.
Colour shifts
Soy wax is naturally off-white and yellows slowly with light and oxygen exposure. Two things accelerate it:
- UV light. A candle on a sunny windowsill will discolour within months.
- Vanillin. Vanilla and vanilla-adjacent notes oxidise and turn the wax cream, then amber, then brown. This is universal to vanilla fragrance in wax — every maker deals with it.
Worth saying plainly about our own line: Earth & Velvet has vanilla in its base, so it will warm in colour over time more than the others will. It doesn't affect the burn or the scent. In a matte black jar you'd have to be looking for it.
Texture
Old soy can develop more frosting and can feel drier or more crumbly at the surface. Cosmetic. It burns the same.
How long is a soy candle actually good for?
| Age from pour | What to expect |
|---|---|
| 0–12 months | Full scent throw. No practical change. |
| 1–2 years | Cold throw softens. Hot throw largely intact. Some colour shift on vanilla-based scents. |
| 2–4 years | Noticeably weaker throw, especially on fresher, lighter scents. Still perfectly safe. Woody and resinous scents hold up best. |
| 4+ years | Often little scent left. Burns fine as an unscented candle. |
Unscented soy and beeswax effectively don't age at all — archaeologists have found intact wax from antiquity. It's the fragrance that has a clock on it, not the wax.
Is it safe to burn an old candle?
Yes, with the same checks you'd give a new one:
- Wick intact and trimmed to 6mm
- No cracks in the glass — see why jars crack
- No debris, dust or insects embedded in the wax surface
- Nothing sticky or separated on the surface
Dust is the one genuinely worth acting on. A layer of household dust on the wax will smell faintly of burning dust on the first light. Wipe the surface with a dry cloth before you light it.
How to store candles properly
- Lid on. The single biggest factor. A lid slows the evaporation of fragrance from the exposed surface and keeps dust off. If your candle didn't come with one, cling film or the original box does most of the job.
- Upright. Soy softens well below its melt point. A jar stored on its side in a warm room will set with a sloped surface.
- Cool and stable. 15–25 °C. Avoid the swings more than any particular temperature — the same principle that drives frosting.
- Out of direct sunlight. UV both fades colour and degrades fragrance compounds. A cupboard beats a windowsill every time.
- Don't refrigerate. The old tip about chilling a candle before burning is unhelpful and encourages cracking through thermal shock.
Reviving a candle that smells weak
If the cold throw has faded but the candle is otherwise fine, burn it properly rather than sniffing it. A full two-hour session with an edge-to-edge melt pool releases fragrance from the whole surface, and most "faded" candles perform much better lit than they smell in the jar. If it's still weak once burning, that's genuine fade — and there's more on the difference between real fade and your own nose adapting in why your candle smells weaker over time.
Frequently asked questions
Do candles expire?
Not in a safety sense. Wax does not spoil and an old candle is safe to burn provided the wick is intact and the glass is undamaged. What degrades is the fragrance, which weakens gradually over a year or more as volatile compounds evaporate from the wax surface.
How long does a soy candle last unused?
A scented soy candle holds its fragrance best for about one to two years from pouring. Beyond that the scent throw weakens progressively, though the candle remains safe to burn indefinitely. Stored lidded, upright, cool and out of sunlight, it will keep noticeably longer.
Why has my candle turned yellow or brown?
Soy wax yellows slowly with exposure to light and oxygen, and vanilla-based fragrances accelerate it because vanillin oxidises and darkens the wax. It's a cosmetic change with no effect on burn or scent. Direct sunlight is the main accelerant, so store candles in a cupboard.
Is it safe to burn a candle that's several years old?
Yes, provided the wick is intact and trimmed to 6mm, the glass has no cracks, and there is no debris embedded in the wax. Wipe household dust off the surface first, or it will smell of burning dust on the first light.
How should candles be stored?
Lidded, upright, at a stable 15 to 25 °C, out of direct sunlight. The lid matters most because it slows fragrance evaporation from the exposed wax surface and keeps dust off. Do not refrigerate candles, as thermal shock encourages the glass to crack.
Thermelis candles ship with a lid, in matte black glass that keeps light off the wax. 7.1 oz for about 35 hours, 10.6 oz for about 50. See the collection.