Chaewon Kang
Children aged 6 months to under 9 years need 2 doses at least 4 weeks apart if they are getting an influenza shot for the first time or had only 1 dose in total by June 30, 2026. Other eligible children get 1 dose. [1] The free flu shot for children in the 2026-2027 season is for children born from January 1, 2012 to August 31, 2026 (aged 6 months or older). The vaccination period runs from 2026.9.21 (Mon) to 2027.4.30 (Fri). [1] (As of: November 2026)
Child flu shot eligibility and dates at a glance
Eligibility is set by date of birth, not by age. From the 2026-2027 season, the program is expanded to age 14 (born in 2012), so children born in 2012 are also included. [1] Start by checking the table below.
| Item | Details |
|---|---|
| Eligible children | Children born January 1, 2012 to August 31, 2026, aged 6 months or older [1] |
| Vaccination period | 2026.9.21 (Mon) to 2027.4.30 (Fri) for both 2-dose and 1-dose children [1] |
| Vaccine provided | Trivalent influenza vaccine [1] |
| Where to get it | Designated medical institutions nationwide [1] |
| Eligibility check | Check on the Vaccination Helper (예방접종 도우미) (nip.kdca.go.kr) [1] |
| Accompanying requirement | Minors must visit with a guardian [1] |
The 1-dose group and the 2-dose group have the same vaccination period. Only the number of doses differs.
Is my child 1 dose or 2 doses: check age and vaccination history
The 2-dose group is children aged 6 months to under 9 years who are getting an influenza vaccine for the first time. They receive 2 doses at least 4 weeks apart. [1] Even if it is not the first time, a child who had only 1 influenza dose in total by June 30, 2026 is also in the 2-dose group. [1] Children under 9 years whose vaccination history is unknown are also in the 2-dose group, with doses at least 4 weeks apart. [2]
Decide in the following order.
- Check whether the child was born between January 1, 2012 and August 31, 2026. [1]
- Check whether the child is at least 6 months old and under 9 years old. A child aged 9 or older is in the 1-dose group. [1]
- If so, check whether this is the first influenza shot or the history is unknown. If either applies, the child is in the 2-dose group. [2]
- If the child has been vaccinated before, check whether they had only 1 dose in total by June 30, 2026. If so, the child is in the 2-dose group. [1]
- If none of these conditions apply, the child is in the 1-dose group. [1]
| Child's condition | Number of doses |
|---|---|
| Aged 6 months to under 9 years, first influenza shot | 2 doses at least 4 weeks apart [1] |
| Under 9 years, only 1 dose in total by June 30, 2026 | 2 doses [1] |
| Under 9 years, vaccination history unknown | 2 doses at least 4 weeks apart [2] |
| Eligible birth group not meeting the conditions above | 1-dose group [1] |
When is the second dose: calculating the 4-week interval
The formula is simple. The second dose is possible from the day that is at least 4 weeks after the first dose. [1] Four weeks is the minimum interval, so you can adjust the schedule within the vaccination period after that. However, the vaccination period ends on 2027.4.30, so you need some margin at the first dose to finish both doses within this period. [1]
| First dose date | Earliest second dose date (first dose plus 4 weeks) | Note |
|---|---|---|
| 2026.9.21 | The day 4 weeks after the start date | Based on the start of the vaccination period [1] |
| November 24 | The day 4 weeks later | Based on the start of the Korea Disease Control and Prevention Agency (질병관리청) intensive vaccination period (November 24 to December 23) [3] |
| December 23 | January 20 of the next year | Based on the last day of the intensive vaccination period [3] |
| 4 weeks before the end date | End of vaccination period, 2027.4.30 | Counted backward from the end of the vaccination period [1] |
Counting backward, the day 4 weeks before the end date of 2027.4.30 is the last day to get the first dose and still finish both. If the first dose is later than this, the earliest second dose date falls outside the vaccination period. The Korea Disease Control and Prevention Agency runs an intensive vaccination period for groups vulnerable to influenza, such as young children and elementary school students. [3] If the first dose is given within the intensive period, the earliest second dose date also falls within the vaccination period.
Antibodies form 2 weeks after the shot: this year's flu situation and timing
Protection does not start right after the shot. It takes about 2 weeks for antibodies to form. [3] For a child getting 2 doses, the effect of both doses is complete only 2 weeks after the second dose, so it is safer to move the schedule earlier than to get vaccinated after the flu starts spreading.
The flu situation is also worth noting. The Korea Disease Control and Prevention Agency said the influenza outbreak is concentrated in children and teenagers, and urged vaccination especially for school-age children. [3] The main circulating virus is type A (H3N2). Some variants have been found, but the vaccine currently being given is still assessed as effective. [3] The worry that "there are variants, so the shot is useless" does not match this assessment. The fact that the vaccination period is open until 2027.4.30 means you can still get vaccinated late. It does not mean you can delay. [1]
What to prepare on the day and cautions after the shot
A minor must visit with a guardian. [1] Check the list below in order.
- First check on the Vaccination Helper whether your child is eligible. [1]
- A guardian visits a designated medical institution nationwide with the child. [1]
- For a 2-dose child, write the earliest second dose date (first dose plus 4 weeks) on your calendar. [1]
- Do not bathe on the day of the shot. [3]
- Remember that about 2 weeks after the shot is the period when antibodies form. [3]
Signs that require contacting a hospital right away should be remembered separately. Contact the medical institution that gave the shot or a nearby pediatric clinic right away if a high fever continues, the face or lips swell, the child has trouble breathing, has a seizure, or is unusually limp and hard to wake. A slightly swollen injection site or a child who is fussier than usual is a common reaction. If you are still worried, ask the vaccination provider.
Frequently asked questions
Q1. Where can I get the shot if I have no foreigner registration number or am staying short term, and cannot get the free shot at a designated medical institution?
Only people who cannot get the free shot at a designated medical institution, such as those without a foreigner registration number or short-term residents, can get vaccinated at a public health center. [2]
Q3. What is the eligibility if there is a pregnant woman in the family?
Children are eligible based on their date of birth. Pregnant women are covered separately under the influenza vaccination program for pregnant women, regardless of the week of pregnancy. [2] Check eligibility for the child and the pregnant woman separately.