You can start being contagious with COVID about 1 to 2 days before any symptoms show up, which is usually around 2–5 days after exposure for many people, though it can be later. Most transmission happens in the couple of days before symptoms and the first few days after they start, and many people are no longer very contagious after about 8–10 days from symptom onset.

Quick Scoop

When you become contagious

  • COVID’s incubation period (time from exposure to symptoms) is typically about 2–14 days, with many people developing symptoms around day 3–5.
  • People can shed virus and infect others about 1–2 days before symptoms begin, meaning some become contagious as early as roughly 2 days after exposure.
  • Even if you never feel sick (asymptomatic), you can still be contagious during this early period.

How long you stay contagious

  • For most mild to moderate cases, people are contagious for about 8–10 days from when symptoms start or from a first positive test.
  • Infectiousness is highest in the early phase: from about 1–2 days before symptoms to the first several days after they begin.
  • Some guidance notes that many people are no longer infectious after about 9–10 days, though a small number—especially with severe illness or weakened immunity—may shed virus longer.

Practical takeaways after an exposure

  • For the first few days after exposure, you may not test positive yet, but you can become contagious before you feel ill, so masking and limiting close contact with high‑risk people is wise.
  • Health agencies commonly advise:
    1. Monitor for symptoms for at least 10 days after exposure.
2. Test several days after exposure (often around day 3–5) and again if symptoms appear.

3. If you get sick or test positive, stay home until symptoms are improving and you’ve been fever‑free for 24 hours without medication, then use extra precautions (masking, distancing) for several more days.

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