TL;DR
The typical Chihuahua lifespan is about 12 years, and many live well into their teens. In a 2024 UK study of 584,734 dogs, Chihuahuas had a median lifespan of 11.8 years, close to the 12.0 years of mixed breeds. But Chihuahuas are also at risk of dying young: in a UK study of Chihuahuas under veterinary care, the median age at death was only 8.2 years, and females outlived males by about three years (10.2 versus 6.9). The most common causes of death were heart disease (18.8%), lower airway disease (16.3%) and traumatic injury (13.8%), and the most common problem in living dogs was dental disease (13.5%). A Chihuahua is a senior from about 8.9 years.
How long do Chihuahuas live?
| Measure | Chihuahua | Mixed breed |
|---|---|---|
| Median lifespan, 2024 UK study (3,848 deaths) | 11.8 years | 12.0 years |
| Median age at death, UK Chihuahua study | 8.2 years | |
| Females / males, UK Chihuahua study | 10.2 / 6.9 years | |
| Life expectancy at birth, UK life tables | 7.91 years | 11.82 years |
| Senior from about (last 25% of lifespan) | 8.9 years | 9 years |
Why do the figures differ so much? The 2024 study looked at a very large group of dogs across many years. The Chihuahua study looked at a young, fast-growing population: the share of UK puppies that were Chihuahuas rose from 1.01% in 2005 to 5.35% in 2016, so many of the dogs that died were young, often from accidents. A Chihuahua that gets safely through its early years has a good chance of reaching its teens. In the Chihuahua study, the middle half of dogs died between 3.5 and 12.1 years.
Chihuahua age in human years
| Dog's age | Life stage | Roughly like a person aged |
|---|---|---|
| 4 years | Mature adult | 27 |
| 5 years | Mature adult | 33 |
| 6 years | Mature adult | 40 |
| 7 years | Mature adult | 47 |
| 8 years | Mature adult | 54 |
| 9 years | Senior | 60 |
| 10 years | Senior | 67 |
| 11 years | Senior | 74 |
| 12 years | Senior, past the median | 80 |
| 13 years | Senior, past the median | 87 |
| 14 years | Senior, past the median | 94 |
| 15 years | Senior, past the median | 100 |
This uses the share of the breed's typical lifespan a dog has lived, compared with US human life expectancy of 79 years. For puppies and young dogs, the DNA-based method in the calculator below is more accurate. Try any age:
Dog age calculator
Enter your dog's age and breed. Choose "Mixed breed" if you are not sure.
Human age (DNA method)
64
From age-related DNA changes in Labradors compared with people (Wang 2020). Least reliable for puppies under a few months.
Same point in a human life
53
Your dog has lived about 67% of the typical 12.0-year lifespan for this group. The same share of a 79.0-year US life expectancy is age 53.
Life stage
Mature adult
AAHA: from maturity until the last 25% of expected lifespan, about 9.0 years for this group.
Mixed breed (crossbreed): median lifespan 12.0 years (95% CI 12.0 to 12.1), senior from about 9.0 years.
Lifespans: UK study of 584,734 dogs (McMillan 2024). Life stages: AAHA. Every dog ages differently; health, weight and lifestyle all matter.
What Chihuahuas die of
In the UK study of 11,647 Chihuahuas:
| Cause of death | Share of deaths |
|---|---|
| Heart disease | 18.8% |
| Lower respiratory tract disease | 16.3% |
| Traumatic injury | 13.8% |
Heart disease
Small dogs are most affected by degenerative mitral valve disease, a leaky heart valve. In a large UK study, Chihuahuas had 6.16 times the odds of being diagnosed with it compared with crossbreeds. Ask your vet to listen for a murmur at every check, especially after about 7 years of age.
Injuries
A dog that weighs a median of 3.4 kg is easily hurt by falls from sofas or arms, being stepped on, or encounters with larger dogs. Traumatic injury was one of the top three causes of death. Ramps, careful handling and supervised play with big dogs save lives.
Common Chihuahua health problems
The most common problems recorded in UK Chihuahuas were:
- Periodontal (gum) disease: 13.5%
- Overweight or obesity: 5.9%
- Retained baby teeth: 5.7%
- Anal sac impaction: 4.9%
- Aggression: 4.2%
Dental problems dominate. A Chihuahua has the same 42 adult teeth as a large dog, crowded into a tiny mouth, and baby teeth that do not fall out trap food and speed up tartar. See how many teeth does a dog have.
How to help a Chihuahua live longer
- Protect it from injury. Use ramps or steps for sofas and beds, hold it securely, and supervise play with larger dogs.
- Look after its teeth from puppyhood. Have retained baby teeth checked at around 6 to 7 months. Brush daily if you can. If you cannot, daily help in food can slow plaque: in a randomized trial of 60 small dogs (mostly Chihuahuas and Miniature Schnauzers), daily treats containing the seaweed Ascophyllum nodosum led to significantly less plaque and tartar over 90 days. Our Daily Dental Cleaning Powder contains 700 mg of Ascophyllum nodosum per 4 g serving and is now available to pre-order.
- Keep it lean. Even half a kilogram is a lot of extra weight for a 3.4 kg dog.
- Ask about the heart at every check-up, and know the warning signs: coughing, breathing fast at rest, tiring easily.
- Keep it warm. Tiny dogs lose heat quickly, so a coat on cold walks and a warm bed help.
- Twice-yearly vet checks from about 8.9 years.
FAQ
How long do Chihuahuas live?
Most Chihuahuas live around 12 years, and many reach their teens. A 2024 UK study of 584,734 dogs found a median lifespan of 11.8 years for the breed.
Do female Chihuahuas live longer than males?
In a UK study of Chihuahuas under veterinary care, females died at a median of 10.2 years and males at 6.9 years. Males were also more likely to be diagnosed with aggression, heart murmurs and ear infections.
Is 12 old for a Chihuahua?
Yes. A Chihuahua is a senior from about 8.9 years, and at 12 it is just past the breed's median lifespan of 11.8 years, roughly like a person aged 80.
What do Chihuahuas usually die from?
In UK veterinary records, the most common causes of death were heart disease (18.8%), lower respiratory tract disease (16.3%) and traumatic injury (13.8%).
What health problems do Chihuahuas have?
Dental disease is the most common, recorded in 13.5% of UK Chihuahuas in a year, along with obesity, retained baby teeth, anal sac problems and heart valve disease.
References
- McMillan KM, et al. Longevity of companion dog breeds: those at risk from early death. Scientific Reports. 2024. PMID: 38302530
- O'Neill DG, et al. Demography and commonly recorded clinical conditions of Chihuahuas under primary veterinary care in the UK in 2016. BMC Veterinary Research. 2020. PMID: 32046714
- Teng KT, et al. Life tables of annual life expectancy and mortality for companion dogs in the United Kingdom. Scientific Reports. 2022. PMID: 35484374
- Mattin MJ, et al. Prevalence of and risk factors for degenerative mitral valve disease in dogs attending primary-care veterinary practices in England. Journal of Veterinary Internal Medicine. 2015. PMID: 25857638
- Gawor J, et al. Effects of edible treats containing Ascophyllum nodosum on the oral health of dogs: a double-blind, randomized, placebo-controlled single-center study. Frontiers in Veterinary Science. 2018. PMID: 30109236
For individual health questions, your veterinarian remains the best partner.
