A standard vape cartridge lasts six months to a year once opened, or up to two years if left sealed in its original packaging. How long yours actually lasts depends on two things: how quickly you use it up (measured in puffs) and how well the oil holds up over time before it degrades.
Puff Count by Cartridge Size
If you’re wondering how many sessions you’ll get out of a cart, the size of the cartridge is what matters most. A typical 500mg (0.5g) cartridge provides around 120 to 150 puffs, with each average drag consuming about 3 to 5mg of oil. A full gram cartridge (1000mg) stretches to roughly 250 to 300 puffs, and smaller 300mg carts deliver about 80 to 100 puffs.
These numbers assume moderate draw lengths. If you take long, deep pulls, you’ll burn through oil faster and get fewer total hits. Voltage matters too: higher heat settings vaporize more oil per puff, which means stronger hits but a shorter-lived cart. Someone who uses a cart casually, a few puffs in the evening, might stretch a half-gram cartridge across several weeks. A heavier user could finish the same cart in a few days.
Shelf Life for Opened and Unopened Carts
Once you start using a cartridge, exposure to air kicks off a slow decline in quality. An opened cart stored in a cool, dry, dark place generally stays fresh for 6 to 12 months. Unopened cartridges hold up better. Disposable vapes last about 12 to 18 months sealed, while refillable cartridges can last up to 24 months in their original packaging thanks to a tighter seal.
These timelines assume reasonable storage conditions. A cart left in a hot car, on a sunny windowsill, or in a humid bathroom will degrade much faster than those numbers suggest.
What Happens to the Oil Over Time
The main active compound in THC cartridges gradually converts into a different cannabinoid called CBN when exposed to air and heat. CBN is far less potent, so the practical effect is that old carts feel weaker. This conversion accelerates significantly at higher temperatures and in acidic conditions. At room temperature, the process is slow enough that a properly stored cart stays reasonably potent for months. But leave it somewhere warm, and the degradation speeds up considerably. Research published in Cannabis and Cannabinoid Research found that the rate of CBN formation roughly tripled when temperatures rose from 50°C to 70°C.
Light exposure also plays a role. UV light can trigger chemical changes in cannabinoids, including converting THC into less desirable forms. This is why keeping carts in a drawer or case rather than out in the open makes a real difference in how long they stay effective.
How to Tell a Cart Has Gone Bad
You don’t need a lab to spot an expired cartridge. The most reliable indicators are visible:
- Color change: Fresh cannabis oil is typically light gold or amber. As oxidation sets in, the oil darkens to a deep brown. This is the first and most obvious sign of aging.
- Viscosity shift: If the oil has become noticeably thicker or unusually runny compared to when you bought it, the chemical composition has changed.
- Taste: A stale, harsh, or burnt flavor, especially one that wasn’t there before, signals degradation. Weak or flat flavor is another sign the active compounds have broken down.
- Smell: If the oil smells off or different from what you remember, trust your nose.
Any one of these signs means the cart is past its peak. Multiple signs together mean it’s time to replace it.
Risks of Using Old Cartridges
An old cart isn’t just weaker. As oil oxidizes, it generates reactive oxygen species, essentially unstable molecules that can damage cells in your lungs. Research published in Toxics found that vape cartridge aerosols triggered significant oxidative stress and inflammatory responses in lung tissue, with degraded or low-quality cartridge contents producing higher levels of volatile organic compounds.
Expired oil can also burn less cleanly, producing harsher vapor that irritates the throat and airways. Users commonly report coughing, burning sensations on the tongue and throat, and stomach upset from old cartridges. The coil itself contributes to this problem: residue buildup on aging hardware means the oil heats unevenly, creating more irritating byproducts.
Hardware Wear and Clogging
Even if the oil inside is still fine, the cartridge hardware has its own lifespan. The heating coil in a vape cartridge degrades with use as residue accumulates on the coil and wicking material. Cotton wicking turns from white to brown, then develops dark spots, which reduces its ability to absorb oil evenly. The result is dry hits, burnt taste, and eventually leaking as the cotton loses its ability to hold liquid altogether.
For refillable cartridges with replaceable coils, the coil typically lasts one to two weeks of regular use, with about 10 days being average. Pre-filled disposable carts are designed so the oil runs out before the coil fails, but if you’re nursing a cart over many months of light use, the hardware may give out before the oil does.
Storage Tips That Actually Matter
Three factors drive cartridge degradation: heat, light, and air. Controlling all three extends the useful life of your cart significantly.
Store cartridges upright in a cool, dark place. A drawer, cabinet, or case at room temperature works well. Avoid leaving carts in your car, near windows, or anywhere temperatures regularly exceed 75°F (24°C). If you won’t be using a cart for a while, keeping it in its original sealed packaging slows air exposure. Some people refrigerate cartridges for long-term storage, which slows chemical degradation, but let the cart return to room temperature before using it to avoid condensation issues.
For carts you’re actively using, keeping the mouthpiece capped between sessions limits the air that reaches the oil. It’s a small step that adds up over weeks of use.