Essential oils are not cheap, because they require a lot of plant material to produce a small amount of oil. Both essential and vegetable oils do not like extreme, or repeated changes in temperature, and having spent your hard earned cash on all those wonderful oils, you need to make sure you look after them properly or their therapeutic properties may be lost.
If you want to get the most out of your little bottles of aromatic goodness, correct storage is most definitely the key to getting the most out of your oils. When stored correctly essential oils can last an extremely long time. Conservatively, you can keep properly stored oils for at least 1 year.
What is the best way to store essential oils and carrier oils? Here are a few easy-to-follow tips to ensure that your essential oils stay at their peak potency.

Choosing the Right Bottle

1. Essential oils should be packaged in dark colored glass, since this filters out the suns ultra-violet light. Exposure to light can cause essential oils to oxidize rather quickly. As this happens, they typically lose their fragrance and any therapeutic qualities they may have had. Today, dark shades of blue, green and violet have become more popular and they all offer some protection to your oils.
2. Under no circumstances should you ever decant your undiluted essential oils into plastic bottles since most oils will eat into, and in some cases, melt the plastic.
3. Make sure the caps are airtight. Exposure to air can cause oils to oxidize just as much as exposure to sunlight. Because of this, it’s important to ensure that your bottles have an airtight seal.
4. Use solid caps instead of rubber bulb-capped lids. Many oil bottles come with a rubber bulb built into the cap. This is to facilitate easier application of the oils inside. These lids may be convenient, but the rubber will deteriorate over time. Even after a relatively short period of storage, the rubber inside the bulb can disintegrate and may even leak down into your oil.

Cool it

With time, most essential oil constituents oxidize, and heat promotes oxidation. So, no matter what the color of bottle is, you should never leave oils in a place where the sun will shine directly on them – like on a window shelf in the bathroom, for example. Over a period of months, this will dramatically speed up the process of oxidation due to them continually heating up and cooling down. So to avoid the damage caused by temperature variations you could store them in the refrigerator if you have the space. Store oils in a refrigerator. Refrigeration is ideal for oil storage. Keeping the oils in a refrigerator will protect them from sunlight, reduce the chances of air exposure, and help keep the oil stable in the cooler temperature. Carrier oils and massage oils will also benefit by being stored in this way. Don’t have the refrigerator setting too cold, anywhere between 5 – 10 degrees Celsius is fine, and much better than on the window-ledge in the kitchen!

If you do not have the space in your fridge, you may wish to consider a storage box of some type to keep your oils in. It does not have to be a fancy box, just something to keep them all together in one place and away from extreme changes in ambient temperature.

Back to safety

Avoid heat sources. Most essential oils are flammable. They’re often made with alcohol, which can quickly catch fire if left near a fire, candle, or stovetop.[11] If properly stored, though, and kept away from sources of heat, your oil should be perfectly safe to keep around the house.

In short, essential oils should ideally be stored in a cool, dark place in small, dark colored glass bottles for optimum shelf life.