I looked up Citizenship physical presence calculator(1. eservices.cic.gc.ca/rescalc/redir.do?redir=faq#Q3 2. cic.gc.ca/english/pdf/kits/citizen/CIT0407E-2.pdf), and based on the info provided, partial days should be countable too:deadbird said:Some caveats:
* You need to stay a full day in Canada to be counted as a day for citizenship purposes. However, you can stay a partial day for maintaining PR. Also understand that if you have to prove residence for PR/citizenship you need to keep meticulous documentation for all your trips.
* You definitely need to hold a Canadian residence, drivers license and plates.
Not sure about whether you need to maintain a US address.
Yes, I plan on maintaining Canadian license and plates as it would be my primary residence. My concern with maintaining US address is for providing it to my employer as I am not sure if a Canadian address would work for that.When calculating an absence, neither the day you leave Canada nor the day you return is considered an absence. Both are counted as days of physical presence. For example, an absence between July 1, 2013 and July 15, 2013 equals 13 days of absence. As another example, if you leave Canada on July 1, 2013 and return on July 2, 2013, this equals 0 days of absence. You must still declare this as an absence.