Border Collies, originally bred for herding sheep along the Scottish borders, are renowned for their intelligence, agility, and boundless energy. Known as one of the most trainable dog breeds, Border Collies are a perfect match for active households. If you’re considering welcoming one of these lively dogs into your life, understanding their growth, weight range, and development stages can help you ensure your Border Collie grows up happy and healthy.
In this guide, we’ll cover essential facts about Border Collie growth, weight expectations, and health tips, so you know what to expect as your puppy matures into an adult.
Quick Overview: Key Facts About Border Collies
Border Collies are intelligent, loyal dogs with a strong protective instinct towards their families. This can sometimes make them wary of strangers or other animals. They are naturally communicative dogs, often barking when excited, stressed, or seeking attention.
With a lifespan of 12 to 15 years, Border Collies can be a long-lasting source of companionship. Their high energy levels and need for mental stimulation make them best suited for homes where they’ll receive ample exercise and interaction.
How Big Do Border Collies Grow?
Border Collies are medium-sized dogs, typically reaching between 18 to 22 inches (45-56 cm) in height and weighing 30 to 55 pounds (13-24 kg) as adults. Both male and female Border Collies usually weigh between 30 to 55 pounds (14 to 25 kg).
Generally, Border Collies reach their full height by 12 months, although they continue filling out in weight until around 15 to 18 months. If you’re curious about your puppy’s adult size, reaching out to your breeder can help, as they may have measurements of the parents or previous litters.
For a comprehensive breed profile, you can visit American Kennel Club’s Border Collie page.
Average Size of Border Collie Varieties
Border Collies come in a range of sizes, with five main categories:
- Toy Border Collie: Weighs around 12 pounds (5.5 kg)
- Small Border Collie: Weighs between 12-25 pounds (5.5-11 kg)
- Medium Border Collie: Weighs between 30 to 55 pounds (14 to 25 kg)
- Large Border Collie: Weighs between 50-100 pounds (22-45 kg)
- Giant Border Collie: Weighs over 100 pounds (45+ kg)
Miniature Border Collies are sometimes produced through unethical breeding practices or by mixing with smaller breeds, resulting in dwarf-like features that are not considered ideal for the breed. Learn more about the ethical breeding practices for Border Collies at PetMD’s Guide on Dog Breeding.
Border Collie Puppy Growth Chart by Weight
Tracking your Border Collie’s growth can help you monitor their development and ensure they’re maintaining a healthy weight. Use the chart below as a reference based on their age and average weight:
Male Border Collie Puppy Growth Chart
Male Border Collies are typically larger, and this chart provides a range of expected weight gains for male puppies. Keep in mind that males generally achieve their adult size a bit later than females.
| Age | Weight (lbs) | Weight (kg) |
| 1 Month | 3 – 5 | 1.3 – 2.2 |
| 2 Months | 5 – 10 | 2.2 – 4.5 |
| 3 Months | 10 – 15 | 4.5 – 6.8 |
| 4 Months | 13 – 18 | 5.8 – 8.1 |
| 6 Months | 20 – 25 | 9 – 11.3 |
| 12 Months | 30 – 55 | 14 – 25 |
| 2 Years | 30 – 55 | 14 – 25 |
Female Border Collie Puppy Growth Chart
Female Border Collies typically weigh less and are slightly shorter than their male counterparts. This growth chart will help you track your female Border Collie’s development from their first month to their second birthday.
| Age | Weight (lbs) | Weight (kg) |
| 1 Month | 2 – 4 | 0.9 – 1.8 |
| 2 Months | 4 – 8 | 1.8 – 3.6 |
| 3 Months | 8 – 12 | 3.6 – 5.4 |
| 4 Months | 11 – 16 | 4.9 – 7.2 |
| 6 Months | 18 – 22 | 8.1 – 9.9 |
| 12 Months | 30 – 55 | 14 – 25 |
| 2 Years | 30 – 55 | 14 – 25 |
Border Collie Puppy Development Stages
Tracking your Border Collie puppy’s growth is crucial for ensuring they’re developing as expected. By understanding their weight milestones, you can monitor their progress and ensure they stay healthy. While every dog grows at its own pace, knowing when your pup should reach certain weight and development stages helps you keep them on track.
Here’s a breakdown of your Border Collie’s growth from birth to adulthood, with some insights into what to expect at each stage.
0- to 4-Week-Old: Newborns and Early Development
At birth, Border Collie puppies are incredibly small, weighing only about 7 to 14 ounces (0.2 to 0.4 kg). Initially, they lose a bit of weight, but within their first 24 hours, they begin to grow rapidly, gaining around half an ounce to 1.5 ounces (0.014 to 0.04 kg) per day. During this period, they are completely dependent on their mother and remain deaf, blind, and toothless.
As they grow, puppies will begin to crawl, open their eyes, and develop their baby teeth. By week 4, they will typically have gained about 3 pounds (1.4 kg). They start to explore their environment and will soon begin interacting with their littermates, marking the beginning of their socialization phase.
4 Weeks (1 Month): The Wobbly Beginnings
At one month, Border Collie puppies are still small, with males weighing between 3 to 5 pounds (1.4 to 2.3 kg) and females ranging from 2 to 4 pounds (0.9 to 1.8 kg). This is a delicate stage, and puppies should remain close to their mother for the first few weeks. During this time, they begin to stand up and take their first wobbly steps. Their senses are developing, and they may start tasting solid food as their taste buds mature.
8 Weeks (2 Months): The Socialization Period
At 8 weeks, your Border Collie puppy enters the socialization phase. By now, they’ll weigh between 4 to 8 pounds (1.8 to 3.6 kg). They’ll start venturing farther from their mother and siblings, playing more independently, and learning about their environment. They’re also being introduced to semi-solid foods and will be weaned off their mother’s milk. It’s a crucial time for exposure to new experiences and sounds, which helps build their confidence.
12 Weeks (3 Months): Learning and Exploring
At three months, Border Collie puppies are beginning to understand the world around them. They’re learning social skills, boundaries, and experiencing various sounds and smells. By this time, male Border Collies will weigh between 10 to 15 pounds (4.5 to 6.8 kg), while females will range from 8 to 12 pounds (3.6 to 5.4 kg). This is also when it’s important to start socializing your puppy and teaching them basic commands and social behaviors.
16 Weeks (4 Months): Transitioning to Adulthood
At 4 months, your puppy enters the juvenile phase, transitioning from baby teeth to adult teeth. Their weight will range between 8 to 16 pounds (3.6 to 7.3 kg). While they’re still growing, the rapid weight gain slows down, and their energy levels increase. Border Collies at this stage are incredibly active, and this is when you’ll see their playful, high-energy nature begin to take shape.
20 Weeks (5 Months): The Adolescent Stage
At five months, Border Collies begin to look more mature. Female puppies weigh between 15 to 26 pounds (6.8 to 11.8 kg), while males range from 19 to 28 pounds (8.6 to 12.7 kg). During this period, they are in their adolescent phase and may exhibit bursts of energy or stubbornness. Their physical development continues rapidly, but they will still need proper training and socialization to guide them into adulthood.
6 Months: The Teenager Phase
At 6 months, your Border Collie is entering adolescence. They will weigh between 19 to 30 pounds (8.6 to 13.6 kg), still growing taller but with a more defined adult appearance. Their energy levels peak, and you’ll notice an increase in appetite as they go through a growth spurt. Their puppy teeth will be replaced by adult teeth, and they’ll be reaching full maturity in terms of motor skills and coordination.
This is the perfect time to start serious training, especially if you plan to use your Border Collie as a working dog. Female Border Collies may begin their estrous cycle, while males will reach sexual maturity closer to 7 months.
1 Year: Reaching Full Height
By the time your Border Collie reaches one year, they’ll likely have hit their full height, although they may continue to fill out and deepen their chest until they are 2.5 to 3 years old.
Male and female Border Collies weigh between 30 to 55 pounds (14 to 25 kg). Some Border Collies may reach full size a bit earlier, while others will continue to grow into their bodies more slowly. The growth plates typically close around 18 months, and your dog will continue to mature until they’re fully developed at 2.5 to 3 years of age.
Key Takeaways:
- Rapid Growth: Border Collies grow quickly, especially in their first six months.
- Socialization: Early experiences and socialization are crucial for a well-rounded adult dog.
- Energy Peaks: Expect a significant increase in energy levels, especially as they enter adolescence.
- Training and Development: Early training will help channel their energy and intelligence into positive behaviors.
By understanding these growth stages, you can help ensure your Border Collie grows up to be a well-adjusted and healthy adult dog. Keep track of their weight and physical milestones to guide them through these important developmental phases.
Health Tips for Border Collie Growth and Development
Border Collies are active, intelligent dogs that require proper care to thrive. Ensuring their growth and development is supported by a balanced diet, regular exercise, and plenty of rest will help keep them healthy and happy throughout their life. Here are some key tips to promote healthy growth for your Border Collie:
1. Exercise: Mental and Physical Stimulation
Border Collies are high-energy dogs that need both physical exercise and mental stimulation to stay healthy. Regular activity not only keeps them in top shape but also helps prevent obesity, which can stress their joints and muscles.
Without enough stimulation, they can become bored, leading to anxiety or destructive behaviors. Aim for daily walks, playtime, and activities that challenge their intelligence, like obedience training or interactive toys.
2. Diet: Fueling Their Active Lifestyle
A high-quality, protein-rich diet is crucial for Border Collie puppies. Protein supports their rapid growth, muscle development, and energy levels. As they mature, maintaining a balanced diet with the right nutrients ensures their muscles and bones continue to develop strong and healthy.
Consulting with your vet about the Best Dog Food for Border Collies can help maintain a healthy weight and support their high-energy lifestyle.
3. Sleep: Rest for Growth
Puppies need plenty of rest to grow properly. Border Collies, like all puppies, should have a quiet, comfortable space to sleep and recharge. Sleep is essential for healthy development and helps them process the day’s experiences.
While Border Collies typically settle into an adult sleep pattern around 18 months, they will still need ample rest throughout their early life to support their growth.
4. Joint Health: Preventing Mobility Issues
Border Collies are prone to joint problems, especially hip dysplasia, due to their active nature. This condition can affect their mobility and quality of life if not managed properly.
To support joint health, ensure your dog is fed a diet that includes nutrients like omega-3 fatty acids and glucosamine. Regular exercise, avoiding excessive jumping, and maintaining a healthy weight can also help prevent stress on their joints. Early screenings with your vet are recommended to detect any potential issues before they develop further.
5. Routine Checkups
Routine vet visits are essential for monitoring your Border Collie’s growth and development. These checkups allow your vet to address any potential health concerns early, ensure your dog’s vaccinations and parasite prevention are up-to-date, and provide guidance on diet, exercise, and general care.
Monitoring Your Border Collie’s Weight
To ensure your Border Collie is within a healthy weight range, monitor their body condition rather than focusing solely on numbers. You should be able to feel their ribs with a slight layer of fat. If the ribs are too prominent, they may be underweight; if difficult to feel, they may be overweight.
For a comprehensive guide to healthy dog weight management, refer to ASPCA’s Dog Health and Weight Guide.
Common Health Issues Impacting Growth
Border Collies can experience health issues that may impact their growth and development. Key conditions include:
- Hip Dysplasia: This genetic condition affects the joints and can cause pain and mobility issues. Regular exercise and weight management are key preventative measures.
- Collie Eye Anomaly (CEA): This inherited eye condition affects retinal health. While incurable, CEA can be managed with regular veterinary care.
- Dental Issues: Regular dental care can prevent chronic conditions. Border Collies are prone to plaque build-up, so regular brushing is recommended.
For detailed insights into these conditions, visit PetMD’s Border Collie Health and Wellness Guide.
Frequently Asked Questions (FAQs)
At What Age is a Border Collie Fully Grown?
Border Collies typically reach full height around 12 months but continue to fill out in muscle and weight until 18 months. Females usually reach physical maturity slightly earlier than males, with males fully maturing around three years old.
When to Spay or Neuter a Border Collie
Experts suggest waiting until Border Collies are at least 6 to 9 months old before neutering, while some recommend waiting until 12-18 months to allow full bone and joint development. Consult your vet for the timing that’s best for your Border Collie’s health and lifestyle.
To learn more about the costs involved, check out this guide on spaying and neutering costs.
Conclusion: Raising a Happy, Healthy Border Collie
Border Collies are an active, loyal breed with medium-sized frames and boundless energy. With proper nutrition, exercise, and regular health check-ups, your Border Collie will grow into a strong, healthy adult. As these dogs are high-energy, they thrive in homes where they can participate in activities that match their agility and intelligence.
Whether you’re just getting to know this breed or preparing for the arrival of a new puppy, Border Collies promise a journey filled with companionship, fun, and plenty of adventures.
To learn more about this incredible breed, explore Border Collie colors and compare Border Collies vs. Australian Shepherds.
For more information on Border Collies, check out Border Collie Society of America. Let us know about your Border Collie experiences in the comments below!