For fall 2023 in the U.S., the updated COVID-19 vaccines (the 2023–2024 “XBB.1.5” formula from Pfizer-BioNTech, Moderna, and later Novavax) became available in mid‑September 2023, with shots rolling out to pharmacies and clinics shortly after regulatory decisions that month.

When will the new COVID vaccine be available in fall 2023?

Quick Scoop

  • Regulators approved the updated 2023–2024 COVID vaccines in early September 2023. The FDA acted on the new mRNA vaccines (Pfizer-BioNTech and Moderna) on September 11, 2023, updating them to target the Omicron XBB.1.5 lineage.
  • CDC recommended them for the public on September 12, 2023. CDC advised that everyone 6 months and older get an updated COVID‑19 vaccine for the fall/winter virus season.
  • Availability started “later that week” in mid‑September 2023. After the CDC vote and director sign‑off, the updated shots began shipping to clinics and pharmacies, with CDC stating they would be available later that week.

In practical terms, most people in the U.S. could start getting the new fall 2023 COVID shot in the second half of September 2023 , and it then functioned much like a seasonal flu shot—offered through fall and winter.

What exactly was “new” in fall 2023?

The fall 2023 vaccines were updated formulations , not an entirely different technology:

  • They switched to a monovalent XBB.1.5 component (instead of the older “bivalent” shots) to better match the Omicron XBB‑lineage variants that dominated by late summer 2023.
  • The goal was to boost protection against circulating strains and reduce severe disease, hospitalization, and death heading into the 2023–24 respiratory virus season.

Major products:

  • Pfizer‑BioNTech (Comirnaty 2023–2024 formula) – approved for ages 12+ and authorized for younger children under emergency use.
  • Moderna (2023–2024 mRNA formula) – similarly updated and authorized/approved by age group.
  • Novavax (updated protein‑based vaccine) – authorized October 3, 2023, for ages 12+ as an alternative for those who preferred a non‑mRNA option.

Timeline at a glance

[3][1] [5][1] [5] [1]
Date (2023) Event What it meant for you
Sept 11 FDA approved/authorized updated Pfizer & Moderna 2023–2024 XBB.1.5 vaccines.Regulatory green light for the new fall shots.
Sept 12 CDC recommended updated COVID vaccines for everyone 6 months and older.Public health guidance to get the new dose for fall/winter.
Mid‑Sept CDC said updated vaccines would be available “later this week.”Pharmacies and clinics started scheduling appointments and giving shots.
Oct 3 FDA authorized updated Novavax XBB.1.5 vaccine for ages 12+.Non‑mRNA option for fall 2023 became available.

How people were expected to use it (fall/winter 2023–24)

Public health agencies framed the fall 2023 shot as a seasonal update , similar to an annual flu shot, rather than an endless series of “boosters.”

  • Who was recommended to get it?
    • CDC: everyone 6 months and older , with particular emphasis on older adults, people with underlying conditions, and those at higher risk for severe disease.
  • Dose pattern:
    • For most people 5+ who had been previously vaccinated, a single updated dose was recommended for the 2023–24 season.
* Some groups (young children, immunocompromised) had more specific schedules and could receive additional doses.

An example scenario:

A healthy 40‑year‑old who had their last COVID shot in 2022 would typically be advised to get one of the updated XBB.1.5 shots in fall 2023 to “reset” their protection for the winter season, much like updating a flu shot each year.

Forum‑style notes and trending context

“So is this a whole ‘new vaccine’ or just another booster?”
In fall 2023, many forum discussions revolved around this exact question. The consensus from experts was that it’s a reformulated, updated dose , targeted to the then‑dominant XBB.1.5 variant, but still using the same mRNA platform (for Pfizer/Moderna) or protein‑subunit platform (for Novavax).

Key talking points that trended in late 2023:

  • Yearly rhythm:
    • People compared the new COVID shot to the annual flu vaccine , and health agencies explicitly leaned into that framing for fall 2023.
  • Mixing with other shots:
    • Many clinics offered COVID and flu shots in the same visit , and public messaging said getting both together was acceptable.
  • Variant worries vs. fatigue:
    • Some posters worried about new variants and waning immunity, while others expressed fatigue with repeated doses.
    • Expert messaging emphasized that the updated fall 2023 shot aimed mainly to prevent severe outcomes , especially in higher‑risk groups, even if mild infections still occurred.

Practical takeaway

If you were asking in real time back in 2023, the answer would have been:

  • “The new fall 2023 COVID vaccines start rolling out in mid‑September 2023, and you’ll likely see appointments open at major pharmacies and clinics from late September onward.”

If you are looking back now (2026), those fall 2023 shots have since been superseded by later seasonal updates (for 2024–25 and beyond), so current guidance in 2026 would focus on the most recent seasonal formula rather than the 2023–24 one.

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