The Ministry of the Attorney General of Ontario advises that claims may be filed, against a defendant…
“…where the party…carries on business…”
Accordingly you should file in the small claims court serving Pearson Airport (“YYZ”) As to where Delta should be served: Unless, like in the USA, Delta has a “legal process service address” in Ontario I would have Delta served at Pearson Airport.
A guide to filing a small claims action in Ontario can be found at:
http://www.attorneygeneral.jus.gov.o...c/b4aClaim.asp
and,
http://www.attorneygeneral.jus.gov.o...a_Claim_EN.pdf
In addition you should consider mailing a complaint to the Canadian Transportation Agency (“CTA”) in Ottawa. Copies of all correspondence between you and Delta must be included with your complaint. The mailing address, and other contact information, for the CTA is at:
https://www.otc-cta.gc.ca/doc.php?sk...ntact&lang=eng
Information as to what types of complaints the CTA will respond to is located at:
https://forms.cta-otc.gc.ca/pta-atc/form_eng.cfm?Info
As a condition of doing business in Canada, Delta Air Lines, like any foreign corporation, must comply with the laws and regulations of the Governments of Canada and Ontario.
Finally, in the event you are successful in any court action or complaint with the CTA, Delta may try to avoid a cash settlement with you by offering flight vouchers. I would strongly advise against accepting such offers. This board has had more than one posting relating problems with using said vouchers. My opinion of flight vouchers is that, regardless of the airline, they’re not worth the paper they’re printed on.