The expiration date of Japanese products (June 6, 2021)

Or the shelf life (unopened) and PAO (Period After Opening) for cosmetics and quasi-drugs

By Sunscreen.cc (@sunscreen.cc)
Published:

This article was originally posted on Reddit on June 6, 2021. I’ve replaced a few links with archive links and made minor formatting changes and corrections, but otherwise haven’t done any editing or updating. Some links are broken, and some of the information in this post may be outdated by now, although I imagine most of it should still be true.

[Guide] The expiration date of Japanese products (shelf life and PAO)

I often see people asking about the expiration date (in terms of both shelf life and PAO, or period after opening) for Japanese products, so I did some research to try and clear up anything I realized I wasn’t entirely sure about. Specific sources aren’t indicated if I’m referring to more than one website (see References section).

Disclaimers: This entire post is pertaining to products made for the Japanese market, and does not account for any potential differences for products made for other countries, even if they’re made in Japan and are from Japanese brands. Also, I’m not an expert and I’m not affiliated with the beauty industry in any way. I’m just a skincare enthusiast who happens to be fluent in Japanese, so if anyone better informed has anything to add or correct, I would appreciate it very much!

Contents

TL;DR, or the rule of thumb

Japanese cosmetics are not required to indicate expiration dates if the product has a shelf life of at least 3 years unopened starting from the manufacturing date or import date, under stable storage conditions. If the manufacturing date is printed on the product, it will often be in the format YYYYMMDD or similar. Opened cosmetics should generally be used within 3–6 months or at least within 1 year after opening, depending on the type of product (higher water content = shorter PAO), unless otherwise indicated. Watch out for any changes in the color, texture, or smell. Note that both the shelf life and PAO can be affected by storage conditions. Also, the shelf life and PAO indicate the periods of time during which the product is guaranteed to work as advertised, and may often actually be fine to use after that (at your own risk).

In other words: The shelf life and PAO are guidelines, not hard-and-fast rules. This is especially true if they aren’t specified for that product. You might want to be more strict about it for products with active ingredients (including sunscreen), anything that can get in your eyes, and anything that doesn’t contain preservatives, but for the most part, if it looks fine and it smells fine, it’s probably fine to keep using it.

ETA again (in January 2022) that I bought a book by a cosmetic chemist YouTuber—he seems more honest and straightforward than most influencers so I thought of it as a kind of donation to help support him—and he says that based on his experience with product stability testing, he would say that most products are safe to use for 1 year after opening, but that you should stop using it if you observe any changes in appearance or smell. A couple of more advanced books I have mention the 3 year shelf life, but don’t seem to specifically discuss PAO at all. They pretty much just say to be observant about the product’s appearance and smell, and to make sure the formulation isn’t separating out or anything.

By product type

Shelf life (unopened): Starting from the manufacturing date or the import date, under stable storage conditions, unless otherwise indicated.

Approximate PAO (opened): Recommended Period After Opening starting from the day you open the product, under stable storage conditions, unless otherwise indicated.

The PAO varies depending on the source (and between different formulas, I’m sure), so I’m giving ballpark figures based on the multiple sources I’ve found, prioritizing articles that are more specific about the types of products they’re referring to. I wouldn’t be surprised if a lot (or maybe even all) of the PAOs are the same as or similar to any other country, but I’m basing this exclusively on articles in Japanese in case there are any differences.

Again, the higher the water content, the shorter the PAO (with mascara and liquid eyeliner set shorter for eye safety). The PAO also tends to be shorter for “clean beauty” products (or “organic” and/or “natural” and/or “additive-free” products in Japanese marketing terms) that contain no preservatives, which often do give expiration dates.

| Product type | Shelf life (unopened) | Approximate PAO (opened) | | --- | --- | --- | | Mascara, liquid eyeliner | At least 3 years | 2–3 months | | Toners, serums (source) | At least 3 years | 3 months | | Emulsions (source) | At least 3 years | 4–5 months | | Sunscreen | At least 3 years | 3–6 months (ideally within “one season” = probably 4 months); might still be fine after 1 year, but no guarantees | | Non-aerosol sunscreen mists (source) | At least 3 years | 1 year | | Aerosol sunscreen sprays (source) | At least 3 years | 1–3 years (ideally within 1 year) | | Other aerosol sprays (source) | At least 3 years | 3 years | | Creams (source) | At least 3 years | 6 months | | Oil cleansers (source) | At least 3 years | 1 year | | Skincare products in general | At least 3 years | 6–12 months (ideally within “one season” = probably 4 months) | | Makeup primers, liquid foundations, concealers, cream eyeshadow, cream blush, lipsticks, lip gloss | At least 3 years | 6–12 months | | Pencil eyeliners, powder eyeshadow, powder blush, powder foundations, face powders | At least 3 years | 1–2 years | | Product samples in simplified packaging (source) | Use ideally within 1 year | ASAP |

Here are the changes you should look out for, according to the articles I’ve seen (linked in the References section):

And you would obviously want to cease using anything that causes any redness, itchiness, swelling, etc. But as I mention later, in practice, a lot of products seem to be fine to use after the typical PAO under stable storage conditions; it’s just that the safety/stability of the product isn’t officially guaranteed after that point.

Personally I’m more willing to overshoot (admittedly by a lot) with makeup products, because I don’t wear makeup every day and there’s just no way I can possibly finish using anything within the recommended PAOs. But again, that’s 100% at my own risk. I do tearfully discard any products that have changed in color/texture/smell, including liquid eyeliners that started drying out before I could get a lot of uses out of them (an especially heartbreaking farewell goes to my excessive UZU eyeliner collection—I got way too excited when they were first released), and haven’t had any problems so far.

How to determine the manufacturing date

This is going to depend on each brand’s specific practices, but the key thing to remember (especially if you’re from a region that uses a different system) is that dates are formatted as YYYY/MM/DD in Japan. In some cases they might use the Japanese calendar for the year, in which this year is Reiwa 3, but I imagine it would usually be the Gregorian calendar, in which this year is 2021. Supposedly the best way to find out is to contact the distributor or manufacturer and to give them the batch code, but I realize this could be an intimidating process if you don’t speak Japanese (and it’s honestly kind of a hassle even if you do). It can be hit or miss anyway, because apparently not all brands will actually give you the manufacturing date.

Here are some formatting examples from brands that do print the manufacturing date (which, again, they aren’t required to if the product’s shelf life is at least 3 years):

Another way to tell whether a product was manufactured within the past 3 years or not is to guess based on their packaging. As most of you know by now, Japanese products are reformulated or at least repackaged fairly frequently. I think we all tend to worry the most about sunscreen; major sunscreen brands seem to reformulate every 2 years or so, and can sometimes even repackage annually. There are also a lot of limited-edition designs, as well as products that are limited editions entirely. The brand’s official website (and/or their official social media acounts) should have images of the newest version of the product, and RatzillaCosme (in English; fewer products but generally more thorough in covering repackagings) and @cosme (in Japanese; more products but might be hard to navigate, and don’t pay too much attention to the overall ratings and rankings because they’re heavily affected by incentivized reviews) are useful resources for checking for previous versions of the same product.

So right now, as of 2021 (and let me know if I’ve somehow screwed up my math):

And so on. (I’m not going to say “definitely expired” because I’m sure many or even most unopened products with no specified expiration date would be safe to use beyond the 3 year mark, provided that they are kept in stable storage conditions.)

There are also websites that can give you manufacturing dates based on the batch code, but I don’t know of any that are based in Japan, and I don’t know whether the dates they display are actually applicable for products made for Japan or not. They also don’t seem to be officially endorsed by any of the brands they cover, so we don’t know for a fact whether they would be accurate for any country. I’ve also seen blog entries by people who claim to have figured out how to determine the manufacturing date based on the batch codes for specific brands, and even though some of them seem to make sense, they’re all unofficial sources and can’t be guaranteed to be correct.

Stable storage conditions

The shelf life and PAO I’ve discussed assume that the product is stored under stable storage conditions. This means the following:

Why most Japanese products don’t have expiration dates

According to Japanese law, cosmetics are not required to give an expiration date if the product is stable and safe to use for more than 3 years after the manufacturing date or import date under stable storage conditions. (I’ve intentionally mistranslated this as “at least 3 years” up to this point to avoid giving the impression that I mean 4+ years.)

To give examples outside of Japan for some perspective, according to the US FDA, “\[t\]here are no U.S. laws or regulations that require cosmetics to have specific shelf lives or have expiration dates on their labels,” and manufacturers are merely responsible for determining the shelf life of their products. Taiwan seems to have the same three-year rule; it’s 30 months in the EU and ASEAN countries, though the EU also requires a PAO for products that have a shelf life longer than 30 months; and Korea seems to require an expiration date and/or PAO and/or manufacturing date for all products, if I’m understanding my source correctly. (I’ve posted links and excerpts in the Laws section.)

As a cosmetic scientist points out in this VoCE article, the shelf life and PAO are the periods of time in which safety can be guaranteed. There are products that end up being safe to use for much longer than the supposed shelf life and PAO, especially if they don’t contain any water. The scientist in the article claims to own a cream that he opened more than 10 years ago and is still safe to use; I don’t know about that, but then again, I too have had a huge jar of petroleum jelly for roughly 5 years in the past, and it never gave me any problems to the end.

I don’t know how they decided on the three-year rule, and this is just my personal perspective, but not indicating a specific expiration date and encouraging consumers to base their judgment on the color/texture/smell can help us avoid being overly cautious with products that are actually still safe to use, and thus avoid creating excess waste. Conversely, it can also help account for any variations in the storage conditions, which can protect both consumers and companies (in that companies would probably be less liable for problems that can be beyond their control). For example, if your sunscreen has degraded earlier than it should after having left it in your car, an expiration date could potentially give you a false sense of safety.

But while this approach can make sense for products we’ve already bought, it kind of leaves us dead in the water regarding products we’ve yet to buy. My tips would be to buy from sellers that you think are trustworthy and are likely to have high turnover rates, and, if you want to be absolutely sure the product was recently manufactured, to make sure to buy the product in the latest packaging.

Edit: I added notes based on a couple of books I bought after I wrote the post, added to the references section below. (January 2022)

Edit 2: Added info about sunscreen mists/sprays and aerosol sprays. (February 2023)

Edit 3: Added 1 year note about sunscreen. Sumisho posted a video where he tests some sunscreens (mostly from Shiseido or Kao/Kanebo) that were opened last year vs. newly repurchased this year, and most of them seemed like they’re still fine to use. This is going to vary wildly depending on the product and how it’s been stored, though, and there are some major caveats regarding his testing methods as well, e.g., he used PMMA plates and UV-sensitive labels, not human skin. (May 2023)

References

Laws

使用の期限第6条　規約第4条第6号に規定する「厚生労働大臣が定める化粧品」とは、医薬品医療機器等法第61条第5号の規定に基づき厚生労働大臣が指定する化粧品とする。ただし、製造又は輸入後適切な保存条件のもとで3年を超えて性状及び品質が安定な化粧品を除く。2 規約第4条第6号に規定する「使用の期限」は、「使用の期限」等の文字を表示し、前項に規定する化粧品の性状及び品質の安定を保証しうる期限について、月単位まで表示する。例　使用の期限平成13年4月　　使用の期限2001.4
Any cosmetic product that has a lifespan of less than 30 months must show a "Best before the end of" date. This can be shown using the "egg timer" symbol followed by the date, or the words, which can be abbreviated to BBE or Exp, followed by the date.

> For products with a lifespan longer than 30 months, cosmetic products must show a “period after opening” time. That is, the time in months when the product will remain in good condition after the consumer has used the product for the first time. A symbol of an open cream jar is usually used instead of words and the time in months can be inside the symbol or alongside it. > Some products do not require any of these times to be shown because the product will not deteriorate in normal use. Examples are aerosols, which are effectively sealed, perfumes, which have a high alochol content, or single use packs.