TORONTO -- Torontonians aged 80 and older are now able to book a COVID-19 vaccination appointment at a city-run mass immunization clinic.

As of Friday afternoon, approximately 133,000 appointments were up for grabs for Toronto residents born in 1941 or earlier on the city’s website.

Appointments begin on Mar. 17 through to Apr. 11 at three mass immunization clinics across the city: The Metro Toronto Convention Center, Scarborough Town Centre and the Toronto Congress Centre.

Today the city also announced that three more city-run sites will be opening in the coming weeks.

Two will open on Mar. 29 at Malvern Community Recreation Centre and Mitchell Field Community Centre, while the third will open at The Hangar on Apr. 5.

The city says three more clinics are preparing to open and are waiting for more vaccine supply. The expected opening dates for these clinics is unknown.

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Tory said the city’s booking portal has been tested to run efficiently but bumps along the road could still occur.

Once residents complete their booking online, users will get a confirmation number and a QR code for their appointments.

People who arrive at one of the open mass immunization clinics without a confirmed appointment will not be vaccinated.

Mayor John Tory spoke to CP24 this morning and said the city’s booking portal has been tested to run efficiently but bumps along the road could still occur.

“For example, in the early going when you open something like this which will happen later this morning there’s a big rush to go on there and you have to make sure that that kind of loading doesn’t cause undue problems,” he said.

“But look, I have to be an optimist about this. I think the thing has been tested, it’s been well put together and hopefully it will work well for people, that’s the idea.”

The city is asking people who are not yet eligible for a vaccine to not visit the booking platform to avoid slowing it down.

Toronto’s registration site kicks off three days ahead of Monday’s launch date for a provincewide portal to book vaccination appointments.

The city will start using that system on Monday but residents will still be able to access the booking platform by visiting the city’s website.

Toronto’s booking portal will not be available from 8 p.m. on Sunday to Monday morning as the city transfers its registration site to the province’s system.

In addition, as of Monday people will be able to book appointments by phone and a call centre will also open up for extra support.

Meanwhile, approximately 25 smaller vaccination clinics will continue to operate today at a number of hospitals and community health-care centres in Toronto for priority groups. Eligible people include seniors living in congregate settings, health-care workers, Indigenous adults and residents aged 80 and older.