CO SB134

Payment card networks are prohibited from charging interchange fees calculated as a percentage of the gross transaction amount unless the tax portion is excluded from that calculation

Exemptions apply to transactions involving cards issued by financial institutions with less than $60 billion in consolidated worldwide assets, or cards branded with Colorado-chartered institutions meeting that asset threshold as of February 1, 2026

Networks must comply by either excluding taxes at settlement, rebating the tax-related fee portion within 30 days, or allowing merchants 180 days to submit tax documentation for credits

Merchants, consumers, or other injured parties may bring civil actions against violating networks, with penalties including actual damages (or triple damages for bad faith conduct), $500 minimum damages, and attorney fees

Takes effect August 12, 2026, subject to possible referendum petition