Rounding Rules for OAS Benefits Clarified

Summary#

The Regulations Amending the Old Age Security Regulations (Miscellaneous Program) (SOR/2026-129) make the rounding rules for certain Old Age Security benefit calculations explicit. The change corrects a drafting omission and came into force on June 12, 2026.

What it does#

• Replaces section 8 of the Old Age Security Regulations to say clearly how to round benefit amounts that are adjusted quarterly.
• Specifies that calculated amounts are rounded to the nearest cent.
• Explains how to handle fractions with three or more decimal digits:
  • if the third digit is less than five, drop the third and later digits;
  • if the third digit is five or greater, increase the second digit by one and drop the rest.
• Explains how to round ratios written as decimal numbers with four digits after the decimal point:
  • if the fourth digit is less than five, drop it;
  • if the fourth digit is five or greater, increase the third digit by one and drop the rest.
• Makes these rounding rules apply explicitly to the Allowance for the Survivor (ALWS) and to the small “top-up” amounts for the Guaranteed Income Supplement (GIS), Allowance (ALW) and ALWS.

Who's affected#

• People receiving the Old Age Security (OAS) pension, Guaranteed Income Supplement (GIS), Allowance (ALW), or Allowance for the Survivor (ALWS) — including those getting the small top-up payments.
• Employment and Social Development Canada staff and the department’s benefit-payment systems that calculate and pay these amounts.
• It is unclear that anyone else (businesses or provinces) will be affected; the change is about how federal benefits are calculated.

Why it matters#

• This removes uncertainty about how tiny fractions of a cent are handled when benefits are calculated. That makes calculations predictable and legally clear.
• In practice, the department’s old systems and the new Cúram IT system were already using the intended rounding method, so the actual amounts people receive are not expected to change. The amendment simply fixes the written rules to match what was already being done.
• For low-income seniors, clear rounding rules mean their small top-ups and benefit adjustments are consistently and transparently calculated.