Square Trust Center
Square's payments security & compliance posture, captured from Square's public secure-payments and PCI compliance pages. Square is the merchant of record and maintains its own PCI certification so sellers do not individually validate compliance; card processing systems meet PCI Data Security Standard Level 1 (the most stringent level, for processors handling 6M+ transactions/year). Sellers who use the Web Payments SDK / hosted surfaces keep card data off their own servers, qualifying for the lightest PCI SAQ A scope. This is the searched, human-verified fill (the automated trust-center probe requires a trust.
Square maintains a public trust center documenting PCI DSS, PCI SAQ A, ISO 27001, and EMVCo compliance.