Rules & documentation

ACSS rule changes enhance payment system processes

These changes took effect on July 27, 2026.

Payments Canada has implemented a series of administrative and operational amendments to the Automated Clearing Settlement System (ACSS) rules. These updates provide expanded definitions and process efficiency.

Payments Canada’s rules, standards and procedure documents are updated regularly and versions posted online are in force. You can contact Payments Canada for confirmation by e-mail at info@payments.ca.

Item Title Updated System
Quick Links - Lynx
High-value payments - Lynx system rules, procedures and by-laws
High-value payment system - Lynx
Association By-law No. 6
Compliance
Retail batch payment system, High-value payment system - Lynx, System by-laws
Association By-law No. 9
Lynx
High-value payment system - Lynx, System by-laws
Best practice
Uniform treatment of wire payments
High-value payment system - Lynx
Best practice
CACPA code straight-through processing (STP) formatting
High-value payment system - Lynx
Guideline
Deduction of charges for the receipt of Lynx payments
High-value payment system - Lynx
Guideline
Misdirected Lynx payments
High-value payment system - Lynx
PRD-001
Settlement exchange transaction (SET)
High-value payment system - Lynx
PRD-002
Procedures for foreign currency transfers within Canada
High-value payment system - Lynx
PRD-003
Procedures for claims and compensation for US dollar and foreign currency transfers within Canada
High-value payment system - Lynx
Rule 1
Interpretation
High-value payment system - Lynx
Rule 2
General
High-value payment system - Lynx