How Long Do MREs Really Last?

MREs are one reliable source of food that is easy to transport, easy to prepare (if it requires any preparation at all) and generally dependable with a long shelf life.

open beef and black beans MRE
open beef and black beans MRE

Ubiquitous in militaries all over the world use them as field rations, This means that they are staple inclusions and survival caches and bug-out bags for preppers.

MREs are famed (or infamous) for lasting basically forever, but even they will still go back after enough time. This begs the question:

What is the shelf life of an MRE?

The typical shelf life of an MRE is around 5 years at 75° F (23° C).

Ambient temperature at the storage location greatly impacts how long they last. MREs kept in temperatures of 120° F (48° C) or greater can spoil in as little as a month whereas keeping MREs in a cool location of 50° F (10° C) can prolong their lifespan to a decade or more.

You probably have plenty of questions about that assertion, and lucky for you we are here with the answers. Keep reading and you’ll learn everything you need to know about the shelf life and storage considerations for MREs.

Don’t MREs Have an Expiration Date?

No, most “mil spec” MREs do not. Unlike the foods that you and me buy at the grocery store, MREs typically do not feature any sort of expiration date or other guideline for freshness.

This can make determining the safe shelf life or even the age of your MREs tricky, though not impossible.

To do that, you’ll need to do a little figuring and also some educated guessing, though in the end determining the suitability of your MREs for human consumption might come down to the sniff or taste test.

MREs Have a Packing or Manufacturer’s Date Instead

Most MREs don’t have an expiration date but instead have a manufacturer’s date, sometimes called the packing date. The code might be just on the box or crate of MREs or it could be printed on each individual pack.

This is a simple, four digit code that is incomprehensible to those not in the know, but it can allow you to suss out when your MREs were made or packed. Armed with that info, you can better guess how safe and sound your next meal is likely to be.

This code is actually pretty common in food production and other manufacturing circles, and is in the form of a Julian date code.

The first digit of the code indicates the last digit of the year that the item in question was produced, while the next three remaining digits represent the day of the year, out of 365 days. Confused? Don’t be.

For instance, let us say your MREs are marked with a code that reads “1112”. Breaking that could down we would interpret it as “2011” and the “112” indicates they were packed or made on the 112th day of that year, so in April sometime.

This system is pretty straightforward and easy to use once you get the hang of it, but there is a potential drawback that you should be aware of.

First off, this system allows for some false identification In out example above, a person might interpret the first “1” in the code to mean 2001, or 1991.

That might put your estimations off by a huge margin! However, if you know generally what era or “generation” your MREs are you should be able to eliminate this issue by deduction.

an MRE next to a bug out bag
an MRE next to a bug out bag

Low Ambient Temperature is Critical for Long Life

As mentioned above the temperature of the location where the MREs stored is the primary factor that affects its shelf life. You probably already knew that MREs are packaged in heavy duty containers and are heavily processed foodstuffs.

That processing includes plenty of preservatives for extending shelf life, but they are not so packed full of chemical witchcraft that they can effectively ignore temperature considerations.

The bottom line is that your MREs shelf life will continually decrease the higher the temperature climbs. At the top end of the spectrum, say in a desert environment or the trunk of a car, your MRE might last only a single month beyond its packing date.

However, if you keep your MREs in a decidedly cool location where temperatures hover around 50°, they could last in excess of 10 years while remaining completely safe to eat. Not bad.

As you probably guessed this gradient ranges up or down with temperature increases or decreases, and MREs do not fare well at all in broiling hot or freezing temperatures, temperatures where they may run the risk of bursting.

Things also get more complicated when MREs are moved from a cool environment into a warmer environment for a length of time, but then reinterred in a cooler environment for long-term storage. How much life did they lose? Do you have any way to track it? This complicates matters.

MRE's Understanding the date code (10 year old MRE)

Not Sure About the Storage Temperature?

If you acquire or otherwise come into possession of a box or crate of MRE’s with unknown provenance you might, rightly, have some concerns about the temperature in which they were stored and the subsequent safety of the MREs in front of you.

Is there any way to tell the condition of the MREs besides crossing your fingers, holding your nose and cracking that seal for some ready-made, ready-to-eat chow?

Not exactly, but your crate of MRE’s might have a monitoring device attached to the outside that can help inform your decision. Look for a small, slightly glossy burgundy red patch that may look like a bullseye. This is what is called the TTI, or ‘time-temperature indicator’.

Generally, these devices feature an inner and outer ring made of temperature sensitive material. When the inner ring, or dot, appears as dark as or darker than the outer ring you know the MREs have been in a high temperature environment for a long time and you should be cautious.

However, these devices are not foolproof and even if they are functioning correctly your MRE’s might still be safe to eat. Keep reading to learn more.

MRE Shelf life and proper avenues for purchasing

Individual Component Shelf Life May Vary!

Further complicating your quest to properly determine how long you can push your MREs in storage is the fact that the individual components in any given MRE pouch will not have the same shelf lives depending on the ingredients!

Talk about a pain in the you-know-where, especially since most MREs have highly varied contents.

In the case of U.S. Military MREs, you can expect an entrée like beef stew, spaghetti or some other pasta, along with a side dish like potatoes, corn, rice or applesauce.

You’ll have a dessert, often in the form of pound cakes or brownies, and also crackers, peanut butter, applesauce and the like.

Other inclusions are candy, gum, sauces, condiments, and non-food items like a flameless heater, napkin, TP and utensils.

There has been no systematic research performed on this topic recently but previous experiments and studies have shown that items with a high dairy or fruit component often go bad, or experience substantial changes in taste or odor before other items.

Meats, breads, and crackers along with dry ingredients like instant coffee, tea and drink mixes usually don’t have to be worried over unless obviously compromised.

However, fruit sauces and dips, cheese spreads and similar items may give up the ghost many months or even years before the rest of the items in the pouch.

Even if you think your MRE is well within the safety zone of edibility, always take care and pay attention to what your eyes, nose and taste buds are telling you when eating any component!

Making the Most of a Variable Shelf Life

You might be depressed to learn that one of your primary foodstuffs that you were counting on to go the distance for many years is likely only to attain a fraction of the shelf life you were expecting in storage. This is a bit of a bummer, but it is important to assess this limitation practically.

Compared to other foods and portable camping or survival meals, MRE’s still demonstrate excellent shelf life, even in the hottest environments.

Consider the fact that if you were going on an overland trip or a lengthy camping expedition in a warm environment you wouldn’t have to worry about your MREs the entire time.

You could not expect to store them in such a temperature for years on end and then dependably eat them when some SHTF event occurs, but the same could be said for many other foods that will require eventual rotation.

One major limitation that is often seen as a deal-breaker by those who would include a MRE or two in a survival bag is the fact that keeping them in the cabin or the trunk of the vehicle is certainly going to expose it to temperatures in excess of 120° F (48° C) in all but the most frigid places, dramatically shortening it shelf life.

This is true, but remind yourself that any food item you would store in such conditions is going to have a tough, tough time remaining safe and edible.

At any rate, if you want to stay prepared in a time of elevated risk, MRE’s are still a great option, especially if you break them down and include only those components that are most suited to high heat storage.

At the very worst, you’ll just need to remember to rotate it out and make a snack or lunch out of one that has been in place for around a month.

Are Expired MREs Safe to Eat?

Considering that MREs don’t have an expiration date, you might say they are never expired and thus always safe to eat. You would technically be right, but in practice that might not be the best way to look at it.

MREs are designed to last a long time and provide adequate nutrition under sometimes trying circumstances, but that doesn’t mean they indestructible or imperishable.

They can still go bad, both in terms of taste and safety, and when that happens you might not want to consume them.

In the case of MREs that are past their recommended storage life according to temperature guidelines, they might be safe to eat or they might not.

Are MREs that are 5, 10, 15 or 20 Years Old Still Safe?

Possibly! If your MREs have been properly stored, meaning not subjected to excessive heat, cold or moisture, or damaged in some way (opened and the contents exposed to the harsh elements) they might still be safe and edible, though perhaps not very palatable, even after a very long time.

In fact, and though you should never try this yourself, there are adventurous culinarians on YouTube that make vids about eating MREs and military rations going all the back to the Cold War and beyond, even World War I!

It turns my stomach just thinking about it, but it goes to show that MREs can last a long, long time and remain edible… if you can stand the taste.

How Will You Know When an MRE is no Longer Safe to Eat?

The deterioration of the food in an MRE will usually be accompanied by typical signs of spoilage common to other prepared and processed foods.

Always be on the lookout for packets and pouches that are swollen, puffy or leaking as these are sure signs that the food has gone bad.

Bacteria emits gas that causes sealed packages to swell ominously, and that is what you are seeing in such cases.

Assuming your MRE shows no obvious signs of bloating or leaking, move on to opening each packet individually. If any of the food has an off-putting smell, odd texture (well, odd for MRE food!) or looks moldy or discolored in any way, it is probably no longer safe to eat.

If all of that checks out so far, go ahead and give the food a tiny taste. If it tastes “off” or rancid or has an unpleasant foul taste, it is time to toss it and move on to your next meal.

Keep in mind, it is entirely possible that some components might be totally fine while others are decayed beyond hope of eating them. Take your time and be thorough before you toss the whole thing out, especially when times are lean!


An MRE will have a typical shelf life of around 5 years if stored in a location with an ambient temperature around 75° F. Higher temperatures will shorten the shelf life, sometimes dramatically so, and colder temperatures will extend shelf life, again often considerably.

Users should keep in mind that the shelf life of individual component items in the MRE might be dramatically longer or shorter than the overall expiry date.

3 thoughts on “How Long Do MREs Really Last?”

  1. I was told by a retired naval seabe ( reservist ) who told me about eating MRI’s while building runways and revetments in Saudi Arabia in the mid to late 80’s. He stated that some of or most of the MRI’s were 10 to 15 yrs old, with some dates being older and they still were ” pretty ” good, considering their age. Was he pulling my leg? Good question

    1. He’s probably not pulling your leg. I was in the army and we regularly ate expired MREs. Not entirely uncommon to eat some 7-10 years old. Use your better judgement before you put things in your mouth.

  2. Hmm just wondering, about 25 yrs ago or so, while on a weekend deployment with a local guard unit, we were given MRE’s to eat ( they were newly manufactured MRE’s at that time, early to mid 90’s ). but at the end of the training date, they had some left over. So at $3 per MRE, I took 6 MREs home with me, they’ve been in the basement in a box or on the cold concrete floor ( but not in any sun light )ever since. Don’t know it they are any good any more. Thought more than once about opening one of them up and checking it out. Maybe eating it ????

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