The best time to get your flu jab in the UK is usually September, October or early November, before flu starts circulating widely. It takes around 10 to 14 days for your body to build protection after vaccination, so getting your jab at the right time can help you stay protected when flu activity picks up in December and January.
In this guide, we’ll explain when the flu vaccine becomes available, who should book early, what to do if you’ve missed the ideal window, and how to book your flu jab at Periville Pharmacy.
When Is the Best Time to Get a Flu Jab in the UK?
The best time to get a flu jab in the UK is from September through to early November, ahead of the main flu season. Booking within this window gives your immune system time to build strong protection before flu activity peaks in December and January, according to NHS guidance.
Why Flu Jab Timing Affects Your Protection
The timing of your vaccination matters because the flu jab doesn’t provide protection straight away, and that protection gradually reduces over time.
It takes around 10 to 14 days for your immune system to build protection after the jab. Getting vaccinated too early may mean your protection starts to decline before flu activity peaks, while waiting too long could leave you exposed before the vaccine has had time to work.
When Is the Flu Vaccine Available This Year?
For the 2026/27 season, flu vaccinations are offered from 1 September 2026 for pregnant women and young children, while most other groups, including everyone aged 65 and over, are invited from 1 October 2026.
This staggered start follows advice from the Joint Committee on Vaccination and Immunisation, which favours vaccinating adults closer to when flu typically starts circulating. The NHS flu programme then runs through to late March.
If you don’t fall into one of the free NHS groups, you don’t need to wait for these dates. Periville Pharmacy also offers a private flu jab service, so you can get vaccinated for a small fee without needing to check your eligibility first.
Who Should Get the Flu Vaccine, and Who Should Book Early?
Anyone in an NHS priority group should try to book as soon as vaccinations open for their group, as appointments can get busy quite quickly.
You may be eligible for a free NHS flu jab if you are:
- Pregnant, at any stage
- Aged 65 or over
- Living with a long-term condition such as asthma, diabetes or heart disease
- A carer, care home resident, or frontline health and social care worker
- A young child, or a child in a clinical risk group
NICE guidance recommends encouraging eligible people to have their free flu jab each year, helping to reduce winter illness and hospital admissions.
Not sure if you’re eligible? Our team can check for you.
What If You’ve Missed the Ideal Flu Jab Window?
It’s not too late. Although September to early November is the preferred window, the NHS flu programme runs until the end of March. Flu can also continue circulating into the new year, so having your vaccination in December or January can still give you valuable protection.
If you haven’t had your flu jab yet, it’s still worth booking now rather than waiting until next season.
Get Your Flu Jab Sorted Before Winter
Getting your flu jab doesn’t have to mean waiting for a GP appointment. You can book at either of our two Periville Pharmacy branches in Grimsby, with appointments available six days a week.
Whether you’re eligible for a free NHS flu jab or would prefer a private vaccination, our clinical team can check your eligibility and help you get protected before winter.
Don’t wait until the flu is already doing the rounds. Book your flu jab appointment today and give yourself one less thing to worry about this winter.
Frequently Asked Questions
When should I get my flu jab in the UK?
The best time to get your flu jab is between September and early November, before flu starts spreading widely through winter.
When is the flu vaccine available for the 2026/27 season?
The flu vaccine becomes available from 1 September 2026 for pregnant women and young children and from 1 October 2026 for most other eligible adults, including those aged 65 and over.
Is it too late to get a flu jab in December or January?
No. While autumn is the ideal time, the NHS flu programme runs until the end of March, so vaccination in December or January still provides worthwhile protection.
How long does it take for the flu jab to work?
It typically takes 10 to 14 days after vaccination for your immune system to build up full protection against flu.
Who is eligible for a free NHS flu jab?
Free NHS flu vaccination is offered to groups including people aged 65 and over, pregnant women, those with certain long-term health conditions, carers, care home residents and frontline health and social care workers.
Can I get a flu jab if I’m not in an eligible NHS group?
Yes. If you don’t qualify for a free NHS flu jab, you can still book a private flu vaccination at Periville Pharmacy.