The NHS said vaccination teams across Sussex are 'working around the clock' to 'deliver vital protection' to as many people as possible in the build up to Christmas.
They are also 'working hard to accelerate the vaccination programme' to offer boosters to all eligible adults by the end of the year.
"This means that if you are yet to have any Covid-19 vaccinations you can come forward now," an NHS spokesperson said.
"Adults can receive a second jab at eight weeks from their first, and you can have your booster at three months from your second vaccine."
Last weekend was a record breaker for the programme, with more than 55,000 vaccinations confirmed to have been delivered in venues across Sussex in vaccination centres, GP surgeries, pharmacies, and community settings, such as churches and football clubs.
In Worthing, more than 230,000 vaccinations have been given in total across the programme, including first, second and booster vaccines. More than 58,000 people have received their booster vaccination.
The NHS spokesperson added: "The best way to get your vaccination is by booking an appointment on the National Booking Service – www.nhs.uk/covid-vaccination or by calling 119 to arrange your appointment.
"Lots of appointments are now available and new appointments are being added every day so please keep trying if you can’t see a service local to you."
Dates and locations for walk-in sessions can be found on the Sussex Health and Care Partnership website.
In Worthing, vaccination services are available at; Durrington Health Centre – book via national booking system or call 119; St Lawrence Surgery – book via national booking system or call 119; The Strand Medical Group – people are being contacted directly by the local team (please do not call the GP practice) and a walk-in service has been set up at Swandean Training Centre – please check opening hours on the Sussex Health and Care Partnership website.
A spokesperson for the Sussex COVID-19 Vaccination Programme said: “It has been a colossal effort to get as many people vaccinated as possible before the end of year and our teams are doing an amazing job to help get people protected and this work is ongoing.
"Last week in Sussex, we delivered 151,000 vaccinations and we aim to increase this number even further this week.
“The build-up to Christmas is a busy time of year for everyone and we’re grateful to those who have made the time to get themselves a booster before the end of the year.
“There are lots of available appointments on the booking system, so don’t delay. It is vital that as many people as possible have their booster to protect themselves and their loved ones against rising cases of the new variant. It is also never too late if you are yet to have your first or second vaccine; please take the time to make sure you are protected.”
The NHS said more than 50,000 people are booked in for appointments in the coming week. It said the number of appointments available for local people across Sussex has 'significantly increased', with more appointments being added to the system every day.
The spokesperson added: "If you have an appointment booked but it isn’t until the new year, you can also bring your appointment forward, just remember to cancel your old appointment so someone else can have it."