The question many non-dog owners ask during colder months is this 'Why does a dog need a coat?' However, many dogs are simply not built to cope with colder temperatures, snow and ice, and any responsible dog owner will take steps to ensure they do not suffer when outdoors. The main reason some dogs need extra protection while others don't is that the layer of fur they possess is of differing lengths and thicknesses. For example, a Siberian Husky is much better suited to cold conditions than a Greyhound with an extremely short coat.
Deciding whether a dog needs a coat or not is down to owner discretion, although vets may also be able to advise if one is required. One of the most obvious signs is that your dog shivers when you go outside; in this case you should definitely invest in a coat to keep them warm and protected. Even if your dog does not shiver when outdoors, there are certain cases where they require some extra help to keep warm. A good example here is older dogs - they often require extra help to keep warm as their tired and worn down bodies struggle to maintain warmth on their own.
At this point it is also worth pointing out that some dogs shouldn't be made to wear a coat as it could actually do more harm than good. For instance, larger breeds with thick coats do not require a coat and if made to wear one would likely be uncomfortable.
Now we have covered why a dog may need to wear a coat when the temperature drops, let's move on to how to choose the right one. First of all you will need to measure your dog; to learn how to do this there are many size guides available to help you. Getting this right is beneficial for both you and your dog - you want them to be comfortable and if it's too big they may be able to pull it off.
The second factor to decide upon is what material the coat should be made of. Do you want a purely cotton sweater for medium warmth, or do you want a partly-acrylic option so that it's waterproof? As well as being able to protect your dog, it's also worth thinking about how often you're willing to wash it and how often it might need replacing. Most owners will go for a suitable waterproof option as it can be worn in all conditions.

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