“[Family (parents, spouse/common law partner and/or children) or friends] who are not Canadian citizens or permanent residents of Canada may require a visa to enter Canada. […] For more information, see [CIC’s] list of Countries and territories whose citizens require visas in order to enter Canada as visitors.”1
Family or friends “must submit [their] application to the Canadian visa office or Visa Application Center (VAC) responsible [in their] area. Consult the relevant visa office or its website regarding accepted methods of submitting applications (for example, general mail, in person, by courier etc.)” and any additional documents that may be required.2
“You may provide your family member or friend a letter of invitation in support of their application. It should explain how you will help the person. For example, you may offer to pay for plane tickets or accommodation. A letter of invitation can help, but it does not guarantee the person will get a visa.”3
Western University students should include a current official western letter (from the Office of the Registrar or their department) with their invitation letter.
Information for the person writing the letter of invitation
"Writing a letter of invitation does not mean you are legally responsible for the visitor once he or she gets to Canada. You should still write the letter in good faith. You must tell the truth and plan to keep the promises you make in the letter.
Send your letter (notarized, if the visa office asks for that) to the person you are inviting to Canada. The person must then send this letter to the Canadian embassy or consulate outside of Canada when he or she applies for a temporary resident visa."4