Cat Heat Cycle: How Long Cats Stay in Heat
A cat in heat is usually receptive for about 7 days (range 1–21). If she isn't mated she goes out of heat for about a week, then cycles again, so during the breeding season a full cycle averages about three weeks (VCA Animal Hospitals).
| Question | Typical answer |
|---|---|
| How long is a cat in heat? | About 7 days on average; anywhere from 1 to 21 days (VCA). |
| How often do cats go into heat? | Repeatedly during the breeding season. If not mated, she is out of heat for about 7 days (2–19), so a full cycle runs 1–6 weeks, average about 3 (VCA). |
| When is the first heat? | Around six months of age on average, varying with the time of year and daylight (VCA). |
| What drives the season? | Longer daylight hours. Cats are "long-day breeders"; the season also varies with geography and temperature (VCA). |
Induced ovulation: why mating changes everything
Dogs ovulate on a schedule. Cats usually don't: in queens, mating triggers the hormone surge that releases the eggs, and one mating often isn't enough to reach that threshold. Pick what happens during this heat and watch where her cycle goes.
Without mating there is usually no ovulation, so no luteal phase follows. Her hormones fall, she goes out of heat for about a week (2–19 days) and then comes back into heat. That is why an unspayed, unmated queen can seem to be in heat constantly all season (VCA).
Simplified for teaching. Sources: Merck Veterinary Manual ("Management of Reproduction of Cats"); VCA ("Estrous Cycles in Cats"); Axnér, "Catteries" in August's Consultations in Feline Internal Medicine (spontaneous ovulation and pseudopregnancy).
A queen in heat can yowl half the night away; if she has you up at 3 a.m. staring out the window, ahaboo has a narrated explainer on why the Moon is the shape it is tonight.
When might she come back into heat?
EstimateUses VCA's interestrus figures: about 7 days, range 2–19.
Signs a cat is in heat
VCA says the signs are mostly behavioural: she may be extra affectionate and rub against things, roll on the floor, call loudly, and some cats urinate more often or spray on vertical surfaces. Unlike dogs, cats usually show little or no discharge.
A heat that doesn't end
The Merck Veterinary Manual says a cat that shows signs of heat continuously for more than 21 days may have ovarian follicular cysts and should see a vet. Very frequent heats are common in the breeding season and are the main reason owners who aren't breeding choose to spay.
Breeding a queen
Because she is an induced ovulator, Merck notes that queens are usually taken to the tom when they show heat and bred several times over 2–3 days. Screen both cats for infections they could pass to kittens, such as FeLV and FIV (Merck). Once she's mated, the cat pregnancy calculator gives her due window.
Questions breeders ask
How long is a cat in heat?
About 7 days on average, but anywhere from 1 to 21 days (VCA).
How often do cats go into heat?
Repeatedly during the breeding season. If she isn't mated she is usually out of heat for about a week before cycling again, so the whole cycle averages about three weeks (VCA).
Do cats bleed when in heat?
Usually not noticeably. The signs of heat in cats are mainly behavioural: calling, rolling, rubbing and sometimes spraying (VCA).
Can a cat get pregnant the first time she's in heat?
Yes. VCA notes a female cat can get pregnant at any time while she is in heat, and the first heat comes at about six months on average.
Why is my cat in heat all the time?
An unmated queen usually doesn't ovulate, so she cycles back into heat about every few weeks through the season. Continuous signs for more than 21 days can point to follicular cysts, so see a vet (Merck).