This is covered in the Prohibited Practices and Methods in the Collection of Debts found below:
http://www.e-laws.gov.on.ca/html/regs/english/elaws_regs_900074_e.htm#BK6
6) No collection agency or collector shall engage in conduct described in any of the following paragraphs with respect to the debtor, the debtor’s spouse, a member of the debtor’s family or household, a relative, neighbour, friend or acquaintance of the debtor, the debtor’s employer, a person who guaranteed the debt or a person mistakenly believed to be the debtor:
1. Make a telephone call or personal call at any of the following times, except at the request of the person being contacted:
i. On a Sunday, other than between the hours of 1 p.m. and 5 p.m. local time of the place where the contact is being made.
ii. On any day of the week other than a Sunday, between the hours of 9 p.m. and 7 a.m. local time of the place where the contact is being made.
iii. Despite subparagraphs i and ii, on any holiday listed in subsection (7).
2. Contact the person more than three times in a seven-day period on behalf of the same creditor, subject to subsections (8) and (9).
3. Publish or threaten to publish the debtor’s failure to pay.
4. Use threatening, profane, intimidating or coercive language.
5. Use undue, excessive or unreasonable pressure.
6. Otherwise communicate in such a manner or with such frequency as to constitute harassment. O. Reg. 103/06, s. 2.
(7) For the purposes of subparagraph 1 iii of subsection (6), the following days are holidays:
1. New Year’s Day.
1.1 Family Day, being the third Monday in February.
2. Good Friday.
3. Revoked: O. Reg. 24/08, s. 5.
4. Victoria Day.
5. Canada Day.
6. Civic Holiday.
7. Labour Day.
8. Thanksgiving Day.
9. Revoked: O. Reg. 24/08, s. 5.
10. Christmas Day.
11. December 26.
12. Any day fixed as a holiday by proclamation of the Governor General or Lieutenant Governor. O. Reg. 103/06, s. 2; O. Reg. 588/07, s. 1; O. Reg. 24/08, s. 5.
(8) For the purposes of paragraph 2 of subsection (6), the following types of contact shall not be counted:
1. Contact made by ordinary mail.
2. Contact consented to or requested by the person being contacted.
3. Contact of a person other than the debtor where the purpose of the
contact is to locate the debtor. O. Reg. 103/06, s. 2.
(9) The prohibition set out in paragraph 2 of subsection (6) does not apply to a collection agency or collector until such time that the collection agency or collector speaks with the person being contacted either in a telephone call or a personal call, but the prohibition applies thereafter. O. Reg. 103/06, s. 2.