Supplementary Estimates are part of the normal parliamentary approval process to ensure that previously planned government initiatives receive the necessary funding to move them forward, therefore meeting the needs of Canadians. They present information to Parliament on the Government of Canada’s spending requirements that were not sufficiently developed in time for inclusion in the Main Estimates, or urgent but unforeseen, such as natural disasters. Supplementary Estimates directly support an appropriation act.
Supplementary Estimates are published throughout the year; each release is identified alphabetically (A, B, C, etc.). In general, Supplementary Estimates (A) are tabled in May and the associated appropriation act is granted royal assent and becomes law in June. These provide federal organizations with the funding they need early in the year. Supplementary Estimates (B) are tabled in late October or early November and the associated appropriation act is granted royal assent in December. Supplementary Estimates (C) are tabled in February and the associated appropriation act is granted royal assent in March.