How Long Does Dog Food Last For? A Guide

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how long does a bag of dog food last

We all prefer freshly prepared food to something from a day or two ago, found lurking at the back of the fridge. Even though it is perfectly edible, we find a varied diet more interesting and appealing.
Like us, your dog obviously deserves fresh tasting food, however, he or she does not need a variety in his or her diet. In fact, when you find a food that your dog enjoys, stay with it – chopping and changing your dog’s diet may result in an upset stomach.
There are two main types of dog food, dry food (kibble) and wet/canned food. You can choose to prepare fresh food for your dog, but most pet owners choose one of the first two food options due to time limitations and convenience. However, this convenience comes at a price, no premium pet food is cheap, so it is important to know how to keep it fresh for as long as possible.

Does Dog Food Go Bad Or Spoil?

Yes! The same as with all cooked food.
Although dry dog food may not resemble the ingredient list shown on the pet food manufacturers packaging, they are all in there. The ingredients are ground up, shaped into the shapes you see on the bag and cooked by a process called extrusion.
Wet dog food is not always in cans, it also includes food sold in foil trays and pouches. All of these are prepared by mixing the ingredients together and then cooked in the container you buy it in.

Causes Of Spoiled Dog Food

Although all life depends on it, one of the three major spoilers of your dog’s food is air. Whether you have decided on dry or wet dog food for your best friend, as soon as you open the dry dog food bag or canned dog food, the air is going to create an environment where bacteria and bugs want to and can live.
We put our food in the fridge for a reason. Warm temperatures increase and accelerate bacterial activity in all food and your dog’s food is no exception.
Another cause of spoiled dog food is moisture. A damp, moist environment helps mould to grow more quickly. Initially moisture may result in a soggy biscuit and then escalate to a mouldy, green piece of bread for you. This is exactly the same for your dog’s food. Even though you cannot see the initial result of a damp environment on your dog’s food, he or she will not enjoy one of the highlights of the day quite as much.

How To Tell If Your Dog’s Food Is Bad

how long does a bag of dog food last

Below are a few indications that your dog’s food is past it’s best and may even result in health issues for your best friend.

A Suspicious Smell

The smell from a newly opened bag of dried, or (especially) canned dog food, probably doesn’t thrill you as much as a newly opened bag of coffee! However, you will quickly recognise the smell and consequently notice if that smell changes. Change is not always for the best and in this case it is a good indication that your dog’s food has gone bad.


When you see mould on your food, you stick it in the bin, without hesitation. Mouldy food contains mycotoxins, which result in food poisoning. Your dog is not immune to the effects of the mycotoxins in mouldy food. The consequences of food poisoning for your dog may include seizures and tremors. Any sign of mould in your dog’s food means the food goes straight in the trash can!

Bugs In Your Dog’s Food

The bug you are most likely to see in your dog’s dry food is the warehouse beetle. The warehouse beetle is a scavenger, a survivor and the female can lay 100 eggs which hatch in under a week. Now we get onto the down side! The warehouse beetle has fine hairs (setae) on its body, which it sheds regularly. In large enough quantities, these fine hairs can cause problems for your dog’s respiratory system and stomach.
Other bugs are readily available!

Exposure To Heat Or Humidity

If your dog’s food is exposed to high temperatures this will quickly lead to his or her food becoming rancid. Rancidity produces a sour smell as the fats and proteins in the food begin to break down and the food becomes more susceptible to contamination by bacteria. Even if you cannot smell the problem, your dog, with his or her far superior sense of smell, probably will. The smell will normally put your dog off eating the food, however, there are hounds who will eat anything!
Humidity is the main cause of mould. You already know the consequences of mould on your dog’s food and your dog. Fortunately, you can see the mould.

Your Dog’s Food Is Past Its Expiry Date

There are three possible dates shown on any canned or dry food. You might see the date of manufacture, which is when it was made. As a rule of thumb, the shelf life of unopened dry dog food is 12-18 months from this date and for wet dog food 2 years, if unopened.
The most usual dates shown are the expiry and best before dates. These are the last dates when the manufacturer guarantees that the food will be safe and edible for your dog. The manufacturer knows best in this situation.
So, always check the expiry date.

Your Dog Refuses To Eat Or Shows Signs Of Being Unwell

signs of bad dog food

All dogs are different but on the whole most dogs look forward to feeding time. So, if your normally greedy hound does not want to eat, this is something to take seriously. The first thing is to go through the check list above with regard to the food. Your dog will instinctively know if the food is not good by how it smells. Another thing to check is that your dog’s water and food bowls are spotlessly clean.
If your dog is showing signs of being unwell, for example a very much reduced activity level, this could be an indication that his or her dog food has gone bad.
However, a dog with no appetite and lethargy means a trip to the vet, if you are sure that the food is not the problem.

How To Make Your Dog’s Food Last

how to know if dog food is bad

Dry dog food, when opened, will usually last for 2 weeks. Wet dog food will last for 2 to 3 days. In order to make your dog’s food last, here are a few simple things you can do. After all, you want to avoid putting food in the trash can.

Protect Your Dog’s Food From Light And Heat

All food, including your dog’s, is affected by exposure to light, by a process called photodegradation. This happens with both natural and artificial light. Photodegradation causes a loss of vitamins in the food and also impairs the taste of the food.
Heat causes the same problems, however, to a lesser extent in dry dog food than wet food.
So, you obviously need to store your best friend’s food in a cool, dark place. If you are using dry food to feed your dog, keep it in it’s original bag, reseal the top and store it somewhere cool. With an opened can of wet dog food, cover it with plastic wrap or cling film and put it in the ‘fridge.
Apparently the light in the fridge does go off when you close the door!

Keep Your Dog’s Dry Food Dry!

how long does dog food last

Once you open that bag with your dog’s food in it, the countdown timer starts. You have one month when the food will be at it’s best, but only if you store it correctly.
As said before, keep the dry food in its original packaging and seal the top. This should then be stored in an airtight container. You can use either metal or plastic containers, (there are many to choose from), or why not repurpose something you may already have.

Look At The Expiry Date

So, now we are going dog food shopping! Bulk buying dog food may seem to be the most economical way to do this. However, not necessarily so.
First consider how much your dog eats each day, this is dependent on his or her size and activity level. As a bag of dry dog food lasts for 2 weeks after it is opened, don’t be tempted to buy a larger bag to save money, if you will be putting some of it in the bin.
So, now it may be more economical to buy two bags of food. This is where the expiry date is important. The second bag still needs to be before the expiry date when you plan to open it.
Exactly the same applies to wet food. Buy the right sized can for your dog’s needs and check the expiry dates on all the cans you buy.


Although this has mainly concentrated on wet and dry dog food, wet dog food and home cooked dog food have the same shelf life and have to be treated in the same way. Put them in the fridge to keep them fresh for your best friend.
So, pet parents, you now have a few tips on how to maintain the nutritional benefits of your dog’s food and the consequences of not doing so.
Bon Appetit!