How Long Are Cats in Heat?

Krista Seraydar, DVM
By Krista Seraydar, DVM on Jun. 30, 2020
How Long Are Cats in Heat?

A heat cycle is the normal cycle of reproduction that occurs in unspayed female cats. Here’s everything you need to know about feline heat cycles and what to expect.

How Long Does a Cat Heat Cycle Last?

Signs of heat will resolve within 24-48 hours of ovulation, which will occur only if a female cat in heat mates.

Otherwise, the average cat will be in “heat” for seven days (ranging from 2-19 days). This cycle can repeat itself every two to three weeks, as long as there are extended daylight hours.

Phases of Heat Cycles in Cats

A cat goes through five phases during a heat cycle:

  • Proestrus: Only lasts one to two days; typically no change in behavior

  • Estrus (“heat”): Lasting an average of seven days (ranges from 2-19 days), this is the stage where you will see behavioral changes in your cat. This is also the stage where your cat will be receptive to male cats and can become pregnant.

  • Interestrus: This period occurs if a cat has not ovulated. It lasts 13-18 days—until proestrus starts again.

  • Diestrus: Occurs when a cat has ovulated (this happens when the female cat mates with a male)

  • Anestrus: This is the absence of any heat cycle. It can occur as a result of fewer daylight hours (may not be seen in indoor cats with exposure to constant light indoors).

At What Age Can Cats Get Pregnant?

The average female cat will first go into heat (or cycle) between 6-9 months of age, but heat cycles can start as early as 4 months of age and as late as 12 months.

Short-haired breeds will typically begin to cycle earlier, while long-haired or larger breeds may not show signs of heat until 18 months of age.

How Often Do Cats Go Into Heat?

If a cat does not become pregnant, she can go into heat as often as every two to three weeks.

When Do Cats Go Into Heat? Is There a Breeding Season?

The number of daylight hours typically has the largest impact on when cats will reach sexual maturity.

Cats normally go into heat when there are 14-16 hours of daylight (natural or artificial). In the Northern hemisphere, this falls from mid-January to mid-October.

What Are the Signs of a Cat in Heat?

During the estrus (heat) phase, a female cat may display changes in behavior such as:

  • Constant, loud vocalizing

  • Rubbing, rolling, increased affection

  • Urine spraying

  • Scratching at doors/windows, trying to escape

  • Placing hind quarters up in the air while flagging her tail—signaling she is receptive to male cats

How to Prevent Your Cat From Going Into Heat

The most effective way to prevent your cat from going into heat and to prevent cat pregnancies is to have her spayed (surgically remove her ovaries and uterus).

Featured Image: Raymond

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Krista Seraydar, DVM


Krista Seraydar, DVM


Dr. Krista Seraydar was born and raised in South Florida. She is a graduate of the University of Florida College of Veterinary Medicine...

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