Please be advised that this site is not affiliated with the Service Canada office.
It was created to provide general SIN information only.
SIN start with number 1 for people in Ontario
1xx Series SIN (Atlantic and Ontario region)
Social Insurance Number applicants in Ontario might have noticed their SIN starts with the number 1 series, which is the same as for people living in the Atlantic region. Social Insurance office started to roll out SIN with 1 series for people who applied for their SIN in the Ontario region in the fall of 2021. This move seems to be because the 4 and 5 series SIN has reached its limit.
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If you want to stay on top of every federal benefit payment date in 2026, we’ve put together a clear and easy-to-follow guide to help you plan ahead with confidence. Explore the full schedule and make sure you never miss a payment by checking out the 2026 Federal Government Benefit Payment Calendar.
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Kaden
July 26, 2022 4:32 pmI applied my SIN in Hamilton back in October and my number start with 145-XXX-XXX, checked online and thought there was a glitched in government system!