Male cats typically finish growing within the first year, but there is variation by breed and individual. Here’s a concise overview:
- Most cats: stop growing by about 12 months.
- Larger or slow-m maturing breeds: may continue to fill out or gain size into 18 months, and in some very large breeds (e.g., Maine Coons) growth can extend further, sometimes up to 2–3 years for final body size and bone development.
- Sex differences: males often reach a larger size than females, with growth plates closing at different times; intact (unneutered) cats can show longer growth periods due to hormonal influences, though nutrition and genetics are primary drivers.
- Practical signs: once growth plates close, vertical growth ceases and you’ll see more filling out in muscle and frame rather than increases in height or length. For most cats, you’ll notice the size plateau around 12–18 months, with some continued minor changes thereafter.
If you’re wondering about a specific cat (breed, size, or health), sharing those details can refine the estimate.
