Unspayed female cats can go into heat (estrus) very frequently—about every 2–3 weeks during their breeding season, with each heat lasting around 6–10 days. Many cats cycle from late winter through fall, and indoor cats with artificial light may show heat cycles almost year‑round.

Quick Scoop: Cat Heat Cycle Basics

  • Most female cats are seasonally polyestrous, meaning they have many cycles in one breeding season rather than just one or two.
  • A typical heat lasts about 6–10 days; if she doesn’t mate, another heat may start again after roughly 1–3 weeks.
  • In many regions, breeding season runs roughly from February to October, so your cat may seem “always in heat” during these months.

How Often Does a Cat Go Into Heat?

  • Once she reaches sexual maturity (often around 4–6 months, sometimes up to 12 months), she can come into heat every 2–3 weeks in season.
  • Some sources describe cycles repeating every 15–21 days, which fits the same general pattern: frequent, closely spaced heats.
  • Because the intervals are so short, unspayed indoor cats—especially those exposed to long hours of light—may appear to be in heat almost continuously.

How Long Does Each Heat Last?

  • Most heats last about 6–7 days, but some can run from a few days up to around 10 days.
  • If a cat mates and ovulates, the heat often ends sooner (around 2–4 days), and pregnancy or a pseudo‑pregnancy may follow.
  • If she doesn’t mate, the cycle ends, she rests briefly, and then another heat begins—hence the “every couple of weeks” pattern.

Why It Feels So Constant

  • Cats are long‑day breeders, so more daylight (and indoor lighting) stimulates repeated heats over many months.
  • Unlike many other animals, they don’t reliably have a long, quiet “off‑season” unless spayed.
  • Because of this, vets often recommend spaying both to prevent constant vocalizing, restlessness, and attempts to escape, and to reduce health risks like pyometra and some reproductive cancers.

If Your Cat Is In Heat Often

  • Talk with a veterinarian about spaying ; it is the only reliable way to stop repeated heat cycles.
  • Until then, keeping her indoors, minimizing access to intact males, and offering calm, quiet spaces and play can help manage stress and disruptive behaviors.

Information gathered from public forums or data available on the internet and portrayed here.