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Puppy Stages: 16-Week-Old Puppy Behavior and Development

Adrienne is a certified dog trainer and former veterinarian assistant who partners with some of the best veterinarians worldwide.

16-week-old puppies are chewing machines. Here's what you can expect from puppies at this time.

16-week-old puppies are chewing machines. Here's what you can expect from puppies at this time.

What to Expect From 16-Week Puppies

If you are wondering what happens when a puppy is 16-weeks-old, most likely you are considering adopting a puppy of this age or are wondering if your 16-week-old puppy's behaviors and development are normal for this age. What happens at this age? What behaviors should you expect?

Remedial Socialization

At 16 weeks, the puppy's grace period for critical socialization has closed. Indeed, this brief window of opportunity according to veterinarian and Animal Behavior PhD, Ian Dunbar, takes place between four and twelve weeks of age. What happens if you missed the boat or your vet recommended you to wait until your dog's series of vaccinations were completed? Karen Overall, Veterinarian, Diplomate of the American College of Veterinary Behavior claims in a handout prepared by the Pet Professional Guild:

"People need to realize that vets don’t know that much about problematic behavior, or maybe even normal behavior. The single biggest reason people relinquish animals to a shelter is a behavioral problem.”

At this point, if you haven't socialized your puppy, you are left with the option of what is known in dog training lingo as "remedial socialization." This doesn't mean you'll have to make up for the missed time and flood your dog with stimuli! This will likely overwhelm your puppy and cause more damage than good. Instead, gradually and systematically expose your dog to people and other dogs.

Make sure you have established a certain level of trust and bond with your puppy. Use high value treats to create positive associations. If your dog appears fearful, respect that, and don't force him to interact—as of yet. Then figure out a way to systematically desensitize and counter-condition him to that fearful stimuli

There are several things going on from a developmental and behavioral standpoint in puppies at this age, in the next paragraph we will go over them.

Notice the curvy hair this 16-week old Lab mix puppy has developed.

Notice the curvy hair this 16-week old Lab mix puppy has developed.


At 16-weeks, puppies still retain several puppy characteristics enough for causing people to "ohhh" and "awwww" at the sight of them. Yet, they are undergoing several physical changes that are gradually morphing them into young adults. They are undergoing rapid growth and are becoming taller and longer, but their minds are still like puppies. At this age, they are also almost reaching half of their adult weight. Following are some developmental stages observed in 16-week-old puppies.

Changing Hairdo

In the article on 12-week-old puppies, we saw how the 12-week puppy still retained some of that soft, puppy hair. Now, one month later, at 16 weeks, you may start seeing a bit of adult hair. In the 16-week old Lab mix in the picture, you can see how she started showing the first zig-zag hair in the back as seen in many adult Labs. A month earlier this was not visible.

Puppy Teething

At 12 weeks, the puppy was starting to lose some of its baby teeth. Now, a month later after losing the incisors, you may start seeing the first adult, permanent incisors coming in by the age of 5 months. The canine teeth may also fall out at around 16 weeks. This is a time where the puppy has sore gums and likes to chew. It's very important to find a safe, age-appropriate puppy chew toys at this point. Chew toys and bones crafted for adult dogs may fracture a puppy's delicate teeth.

Bladder Control

Those bowels and bladders are now starting to gain more control. Where at 12 weeks, puppies were able to hold it for two to four hours, now they can hold it even up to about five hours. Most puppies at this age can hold it all night. Crate training should continue if this is the chosen method used for potty training.

At 16 weeks, puppies are ready to start some training.

At 16 weeks, puppies are ready to start some training.

16 week old puppy learning some basic commands.

16 week old puppy learning some basic commands.


There are many behavior changes taking place in these puppies. As usual, they will have boundless energy and will engage in lots of play. Puppy owners may feel overwhelmed at times by boisterous activity. This is a good time to keep the mind stimulated through training and appropriate play.

Pups Become Warier

As mentioned, this is the time when the window for socialization closes. This socialization phase during which dogs have less fear of the unknown has a distinct purpose in nature. Respected dog trainer and author Jean Donaldson, explains in her book "The Culture Clash," that this brief "window of time” is there so young pups have the chance to become better acclimated (the correct term is habituate) to sights, sounds and experiences within their surroundings. It is meant to be there so animals aren't spooked by harmless stimuli such as the trees, rocks, and birds chirping. Then once, this window is closed, animals start becoming more wary of novel stimuli. This suspicion has an adaptive function. It helps increase the chances for the pups' survival because it prevents them from getting in contact with stimuli that may harm.

Curious Rovers

The saying "curiosity killed the cat" may apply to puppies as well. During this time, puppies are curious about learning about their environment which makes them more likely to get into things and into trouble. Keep an eagle eye on what your puppy tries to eat in the yard and on walks, at home, make sure your home is puppy proofed. At the same time, puppies may have moments where they are fearful of things. They may move tentatively towards new objects and may be intimidated by noises. It's important that they are allowed to investigate scary stimuli on their own and that they're praised for taking initiative.

Activity Levels

At 16-weeks, puppies are still a bit clumsy, but they are getting better at coordinating their movements. Most have boundless energy and are eager to romp, play and jump for a good part of the day. Fortunately, at this age, they also tend to sleep a lot!

Further Reading

This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.

Questions & Answers

Question: When are puppies considered fully grown?

Answer: In general, puppies reach the adolescent stage at around 6 months. At this time, puppies should have all their adult teeth in. After the adolescent stage is over they are considered adults once they are fully grown. Generally, puppies are considered adults by the time they are 24 months, but of course, there are quite some breed variances. Some smaller dogs and medium can be considered adults between 12 and 15 months, while larger dogs may be considered adults by 24 months or even considerably more in giant dog breeds.

© 2013 Adrienne Farricelli


Lyla on July 29, 2020:

i think dogs liveing outside is a bad idea .

Mindy on September 23, 2018:

Renee, "Vets know nothing about behavior in dogs" is a statement from Karen Overall who is a veterinary behaviorist. A very reputable reference, there as veterinary behaviorists are veterinarians who specialize in behavior. Moral of the story, dogs can and do get potentially fatal disease, but socialization is still very important and it can be done safely. Please get more educated on how to do this.

Renee on June 04, 2018:

“Vets know nothing about behavior in dogs.” Single most hysterical line in this article. Please DO NOT introduce your puppy to unknown dogs before completing vaccines. 16 week old puppies can socialize just fine it’s not like if you socialize a 16 week old puppy it’s forever dog aggressive and won’t know how to interact. Parvovirus and kennel cough are potential fatal diseases in puppies... get your priorities in check

Dee on June 03, 2017:

What kind of puppy is featued in the first photo? I just adopted a puppy that is strikenly similar!

Adrienne Farricelli (author) on May 27, 2013:

Yes! often dog owners can't wait for the puppy stage to be over and then bam!, they are hit hard with the teenager stage, which is also sadly the age dogs are more often surrendered to the shelter:(

Heidi Thorne from Chicago Area on May 27, 2013:

Glad my dogs are waaaayyy beyond this puppy-proofing stage. But still, gotta watch 'em. They never really grow up. :) Love the bit about puppy 'do. Stylin'!

After this stage, they get into what I call the teenage-jerk stage at 6 months. So enjoy the 16-weeker!

Adrienne Farricelli (author) on May 26, 2013:

Thank you for stopping by Yuliss. Every puppy and dog assigned to me always teaches me something new. They're like open books.

Yuliss on May 25, 2013:

This was a really informative post on puppy behaviour. Thanks for sharing your knowledge:)