Puppy Milestones: A Timeline of their First Year

By: Kelli Rascoe & Trupanion Staff / Updated Jan 5, 2023

Congratulations on bringing a new puppy into the family! Your dog will give you tons of laughs, love, and memories, and you probably can’t wait to get started. With patience and consistent training, you can establish a strong bond with your new pet and have a best friend for many years to come.

But first, you’ll need to get through your puppy’s first year of life. While your veterinarian can help fill you in on your new puppy’s medical needs, it helps to know what to expect as the weeks and months go by.

Puppy stages to watch for

Dogs go through key stages of growth during their first year of life. Watch closely for these milestones and talk with your veterinarian if you suspect anything is wrong.

Puppy’s first few weeks

From birth to approximately four weeks of age, puppies are still very reliant on their mother and should not be removed from her care (if possible). In fact, most reputable breeders will not permit puppies to be adopted this early in their lifespan. As a result, puppies are most influenced by their mother and littermates at this early stage in life. That said, personality traits and distinctive physical behaviors won’t be apparent just yet.

There are certain physical developments you can watch for, however. While touch and taste are present at birth, it’s around two to four weeks of age that puppies’ eyes open. Their baby teeth also break out at this time, and puppies also develop hearing and a keen sense of smell.

4 weeks to 4 months

Puppies’ social skills will begin to form, and by eight weeks of age they’ll be ready to go to new homes. At this time, they should have developed an inhibited bite and physical coordination, although some training and practice will still be needed in these areas.

Start by sitting down on the floor of a hallway with your back against the wall. Next, create a human hurdle by placing your feet up against the wall across from you. Throw treats or a toy down the hallway to make your dog jump back and forth over your legs, and make sure to follow the motto “low and slow” before challenging your dog to jump higher.

As your puppy adjusts to their new environment and the new humans around them, be aware that they may show signs of fear. Now is a key time to practice patience and provide plenty of positive encouragement.

4 to 6 months

Your puppy’s baby teeth (deciduous teeth) will fall out during this time to make way for their adult teeth, so you can expect plenty of chew time. Puppies chew both to relieve irritation in their mouths and to explore the world around them. So, be sure to provide plenty of puppy-safe chew toys and discourage munching on furniture and unsafe household items. Your puppy’s adult teeth should be entirely in by the time they are six months old.

Keep in mind that your puppy may still display signs of fear during this life stage. They may also become territorial. Proper dog training is crucial at this time to help your puppy learn their place in the pack (which will help them feel more secure) and discourage unsafe behavior.

6 to 9 months

Both male and female puppies can start displaying signs of sexual behavior at this stage. Female puppies can go into heat for the first time, which will mean they have reached sexual maturity and can get pregnant. So, if you haven’t discussed it with your veterinarian already, now is an important time to determine if you will be spaying or neutering your pet.

In the meantime, you can expect your pup to continue testing their place in the household. They may become bolder and may even enter another chewing phase. Keep up with training, and gently but firmly reinforce their place in the pack. Ensuring your puppy has plenty of toys and gets regular exercise will also help.

10 to 12 months

Your puppy will be noticeably bigger than they were months earlier, but they will still have some growing to do before they reach their full size.