Feeding
When should I switch my puppy to adult food?
Small dogs switch at around 9–12 months. Giant breeds should stay on growth food until 18–24 months. Getting this wrong matters most for big dogs.
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The schedule by size
| Adult size | Switch at | Why |
|---|---|---|
| Toy / small (<20 lb) | 9–12 months | Growth largely complete |
| Medium (20–50 lb) | 12–14 months | Bone growth finishing |
| Large (50–90 lb) | 14–18 months | Growth plates still open |
| Giant (90 lb+) | 18–24 months | Growth continues much longer |
Why large breeds switch later
Puppy growth diets are formulated with a controlled calcium-to-phosphorus ratio and calorie density designed for controlled growth. Switching a large-breed puppy to adult food too early can mean energy and mineral levels that don't match the dog's stage of skeletal development. For giant breeds this is a real orthopaedic consideration, not a marketing talking point.
Signs the puppy is ready: growth has visibly slowed, the body condition is stable, and the dog has reached the age range for its size. Not a sign: reaching a certain weight on a certain date. Growth rate varies enormously.
How to transition
- Days 1–2: 75% old food, 25% new
- Days 3–4: 50 / 50
- Days 5–6: 25% old, 75% new
- Day 7: all new food
Slower is fine. If diarrhoea appears, hold at the previous ratio for three days and continue. Sudden switches are a common cause of upset stomach and a common reason owners blame the new food.
Choose adult food on the AAFCO statement
Look for "adult maintenance" — not "all life stages", which is a growth-compliant claim. Compare calorie density, because a denser food means smaller portions.
Questions people ask
When should I switch my puppy to adult food?
Small breeds around 9–12 months, medium 12–14, large 14–18, giant breeds 18–24 months.
Why do large breeds stay on puppy food longer?
Their skeleton develops for much longer, and growth diets control calcium, phosphorus and calories for controlled growth.
How do I transition to adult food?
Over about seven days, mixing old and new 75/25, 50/50, 25/75. Slow down if diarrhoea appears.
Should I use 'all life stages' food instead?
Only if you want one food for multiple dogs. 'Adult maintenance' is the correct claim for an adult dog.