At how many months is a cat considered one year old?

A cat is considered one year old at 12 months, which is roughly equal to a human of 15 to 18 years. Cats usually become sexually mature at 6 to 8 months and have their first heat, but their bodies are not yet fully developed, so they should not be bred at that time.

Generally, a cat goes into heat a second time after one year of age, at which point it can be bred. If you do not plan to breed the cat, you can also have it spayed at a veterinary hospital, which avoids heat-season howling, inappropriate urination and irritable moods.