The journey from pup to grown-up: When is a puppy considered an adult dog?

pup hanging on the side of the wall


Puppies are bundles of joy, full of energy, and bursting with life. However, they grow up quickly, leaving many pet owners wondering, "when is a puppy considered an adult dog?".

Your puppy is considered an adult when they've grown into their full size and reached sexual maturity. However, larger breeds may take up to two years to fully mature. 

Puppyhood: The early days

Puppy development is an exciting, albeit challenging time filled with rapid growth and learning. A puppy's first few months are a whirlwind of new experiences and lessons. They learn basic obedience, socialisation, and house training during this time.

The first eight weeks of a puppy's life are crucial for their development. This is when they learn to interact with humans, other animals, and their environment. It's also the time when they should receive their initial vaccinations to protect them from harmful viruses.

Adolescence: The transitional phase

Adolescence in dogs starts around six to eighteen months of age. This is a time of hormonal changes and behavioural shifts, often compared to the 'teenage' phase in humans. Young dogs might show signs of rebellion, excessive sniffing or humping, territorial behaviour, increased anxiety, and social changes.

During this stage, your puppy's training might seem forgotten or even ignored but this phase is vital to become an adult dog. However, it's essential to persevere with gentle and consistent methods to help them navigate this challenging phase. It's also the time when female dogs experience their first season (heat) and male dogs may start to show more interest in scent marking.

Adulthood: The mature stage

When a pup has fully matured and grown into an adult dog, they reach emotional maturity, and their high energy levels as a puppy should have levelled out. The training invested during the early stages of their lives begins to pay off. By now, dogs should be fully house trained and understand the behaviours expected from them. However, they still retain their playful nature and love for exploration.

How long is a dog a puppy mentally?

While your puppy might physically mature around the age of one to two years, mentally, they might still exhibit puppy-like behaviour. The answer to this varies greatly, with some dogs retaining their playful, puppy-like behaviour well into their adult years.

Is your puppy becoming an adult dog? Signs to look out for

Identifying signs of your puppy transitioning into adulthood can be helpful in understanding their changing needs. Here are some indications that your puppy may be leaving their puppyhood behind:

  1. Loss of puppy teeth: Most dogs' adult teeth will be in place by about six months of age. This is a good time to start thinking about dental care.
  2. Reduced destructive behaviour: As young dogs age, they may chew inappropriate things less frequently as they get older and their adult teeth come in, and their need to explore their environment decreases.
  3. Decreased appetite: Puppies burn through a lot of energy and need a high-protein, high-fat diet. Once they're fully grown, they should switch to adult dog food that meets their nutritional needs and prevents them from becoming overweight.
  4. Sexual maturity: Most dogs become sexually mature by six months of age. This is when your vet may recommend spaying or neutering your pet.
  5. Reduced accidents: As dogs mature, they're physically able to hold their urine and faeces for longer periods, leading to less house-soiling.
  6. Change in social behaviour: Older dogs may become annoyed with younger puppies jumping all over them, so keep that in mind when walking past a stranger on the street with a little pup who may want to greet your dog.
  7. Change in coat: Puppy fur can begin to fall out around six months of age, and it may take another six months to one year for the full adult coat to replace the puppy coat. Prepare yourself for taking care of your dogs coat through our guide.
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Understanding specific breed growth rates

Growth rates can differ significantly among dog breeds. Small breed dogs typically reach full maturity faster than large breed dogs. For example, extra-small breeds (up to 10kg) may reach adulthood at eight months, while giant breeds (45-90kg) may take 18 to 24 months to fully mature. If you're still deciding which dog breed is right for you, find our useful guide on choosing the right breed.

Puppy nutritional needs: the shift from puppy to adult dog food

Puppies require unique nutritional needs compared to adult dogs. They need a diet rich in protein and healthy fats to support their rapid development and growth. As they mature, their food should transition from puppy food to adult food. This transition should be done gradually over a week to help their stomachs adjust and prevent upset.

The importance of regular vet checks

Regular vet checks are crucial throughout your pet's life. Puppies require a series of vaccinations starting at six to eight weeks of age. Healthy adult dogs typically only need to visit a vet once a year for an annual wellness check. It’s also important to get the right pet insurance.

To get a puppy insurance quote for your furry friend, you can get a quote through our website. If you would like to talk to one of our dog insurance specialists, you can get in touch with us on 0330 102 5748.

Exercise requirements for puppies and adult dogs

Laughing, smiling, happy puppy

An adult dog's exercise needs vary depending on size, breed, sex, age, and health. Some small breeds can meet their exercise requirements by simply following you around the house and engaging in occasional play, while larger dogs tend to need at least 30 minutes a day of vigorous activity.

The role of dog supplies in your puppy's development

As your puppy grows, you may need to invest in new dog supplies. A larger collar and leash, bigger food and water dishes, a roomier bed, a larger crate or carrier, and new toys that are both bigger and sturdier to withstand rougher play might be necessary.

At what point is a puppy considered an adult?

Determining exactly when a puppy is considered an adult can vary from breed to breed. It's generally agreed that a dog is no longer a puppy and enters adulthood somewhere between one to two years of age. However, larger breeds may take longer to reach full maturity.

Understanding when a puppy is considered an adult dog is important for every pet owner. As your puppy grows, their needs will change, and understanding these shifts can help ensure they transition into adulthood healthily and happily.

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