If people tested positive they could also get a PCR test there, and await the result.
The best thing people can do to get a free test is to pre-register online, Whanganui DHB engagement lead Rhonda Morris said.
They will be given a number and can pick the kit up by car or on foot.
"We had everything from people on foot to bicycles yesterday," Morris said.
People can also just turn up and have a chat, to find out whether they are entitled to a kit.
People staffing the sites are wearing full PPE, and Morris hasn't heard of any who have contracted Omicron while on the job.
Nationally, there were 15,161 new community cases of Covid-19, which the ministry reports as "another day" overall daily case numbers decreased from the previous day.
On Saturday there were 18,833 new cases announced.
In neighbouring Taranaki and MidCentral DHB areas there were 239 and 378 new cases respectively.
The total number of active cases is 222,011.
The ministry reported another death on Sunday, after five were reported on Saturday.
Public health officials considered the decrease in cases could be related to delays in people self-reporting Rapid Antigen Test results, even if it is a negative result.
"It is essential we have as much information as possible to inform public health decision-making," the ministry said.
"If you take a Rapid Antigen Test, report the result online through my COVID Record."
Instructions for self-reporting RAT results can be found on the Unite Against Covid website.
- Additional reporting Laurel Stowell
