RSV season usually starts in the fall and peaks in the winter, but exact timing can shift a bit each year and by region.

When is RSV season?

  • In most of the continental U.S., RSV season generally runs from October through March or April , with the highest activity in December and January.
  • During the COVID-19 years, RSV seasons were disrupted, with some surges starting as early as late spring or summer, but recent data suggest things are trending back toward the usual winter peak.
  • Places like Florida, Alaska, and some tropical or subtropical areas can have earlier, longer, or less predictable RSV seasons, so timing there may not match the rest of the U.S.

A simple way to think of it: in a typical year, RSV is a “cold‑weather virus,” ramping up in mid‑fall, peaking around the winter holidays, and easing off by early spring.

Why the timing matters

  • High‑risk groups (young infants, older adults, and people with chronic heart or lung disease) are more likely to have serious illness during RSV season.
  • New RSV preventive options (like long‑acting antibodies for infants and vaccines for older adults and some pregnant people) are often timed before the expected start of local RSV activity.
  • Because seasons can shift, public‑health agencies track RSV activity and update clinicians each year about when local circulation is picking up.

What this means for you (2025–2026)

  • For the current 2025–2026 period, RSV activity in the U.S. has again been concentrated in the late fall and winter months , lining up more closely with the traditional October–March window.
  • If you live outside the continental U.S. or in regions with different climate patterns, local RSV timing may differ, so checking your local health department or healthcare provider is important.

TL;DR: RSV season is typically fall through early spring, peaking in winter , but exact start and end dates depend on the year and where you live.

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