Have you filed your tax return?

"What is the GIS?"

The Guaranteed Income Supplement (GIS) is a monthly non-taxable benefit calculated based on income. It is paid to low-income Canadian residents who receive Old Age Security (OAS) . GIS benefits are automatically renewed in July each year, provided that the client files an income tax return by April 30th.

Source : Guaranteed Income Supplement - Canada.ca

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Guaranteed Income Supplement - Information

Income Tax Assistance - Volunteer Program