Walk-in clinics are running for two weeks in locations across the region before the spring COVID-19 vaccination programme comes to an end on Monday, June 30.
Health officials are urging eligible individuals to take advantage of this service if they have missed their original appointment, lost their invitation, or did not receive one.
This applies to anyone in North Wales who will be 75 or older by June 30.
People aged six months and older with weakened immune systems due to health conditions or medical treatments are also eligible to walk in for a vaccine.
The health board has posted details of the locations offering these walk-in vaccinations, along with the dates and times of the clinics.
Officials emphasise that immunity against COVID-19 decreases over time, and research indicates that getting vaccinated is crucial for the most vulnerable in the community to enhance their protection against the virus.
The health board also expressed gratitude to the thousands of family members and friends who have helped eligible older people receive the COVID-19 vaccine this Spring.
Those who have already received a postal invitation are encouraged to attend their appointment at the specified date and time.
People are reminded to check their letters carefully, as the venue may differ from previous vaccination programmes.
If unable to attend, appointments can be rescheduled by calling 03000 840004 or emailing BCU.SROCovid19VaccinationProgramme@wales.nhs.uk.
Teams continue to administer thousands of vaccines every week at various community vaccination centres, including community halls, sports grounds, and leisure centres.
They also visit care homes and housebound individuals to offer them the COVID-19 vaccine.
Since the start of the programme in April, approximately 50,000 people have received the vaccine.
More information about the spring Covid-19 vaccination programme in North Wales can be viewed at bcuhb.nhs.wales/health-advice/vaccinations/covid-19/