---
title: "Tracking customer spend in an omnichannel or multiprocessor environment"
description: "Merchants operating across websites, mobile apps, physical stores, and multiple payment processors struggle to connect spending because customers use physical cards, digital wallets, and tokenized methods. Payment Account Reference (PAR), a 29-character alphanumeric identifier introduced by EMVCo, provides a non-financial, non-reversible reference that maps one PAN to multiple tokens without exposing sensitive payment data. Because the PAR is independent of payment method and processor, merchants can link transactions across channels and preserve continuity when a card is replaced with a new PAN. The post presents an omnichannel retail example and describes potential benefits including unified customer profiles, personalization, cross-channel reconciliation, reduced PAN-related PCI burden, and processor flexibility."
---

# Tracking customer spend in an omnichannel or multiprocessor environment

[Stripe](https://yomu.fyi/company/stripe) · Andrew Robinson · Feb 19, 2025

**Type:** Explainer

## Summary

Merchants operating across websites, mobile apps, physical stores, and multiple payment processors struggle to connect spending because customers use physical cards, digital wallets, and tokenized methods. Payment Account Reference (PAR), a 29-character alphanumeric identifier introduced by EMVCo, provides a non-financial, non-reversible reference that maps one PAN to multiple tokens without exposing sensitive payment data. Because the PAR is independent of payment method and processor, merchants can link transactions across channels and preserve continuity when a card is replaced with a new PAN. The post presents an omnichannel retail example and describes potential benefits including unified customer profiles, personalization, cross-channel reconciliation, reduced PAN-related PCI burden, and processor flexibility.

## Context

Merchants need a complete view of customer spending across channels, payment methods, and processors, but fragmented payment systems and tokenized credentials make it difficult to connect transactions. PAN storage also creates significant PCI DSS obligations, while token changes can disrupt transaction linking.

## Approach / What changed

Use the Payment Account Reference, a 29-character alphanumeric identifier from EMVCo, as a stable, non-financial reference. PAR links one PAN with multiple tokens and remains consistent across payment methods, channels, processors, and the replacement of a card with a new PAN, allowing merchants to connect transaction histories without storing PANs.

## Takeaways

- PAR has a one-to-one relationship with a PAN and a one-to-many relationship with tokens, allowing physical-card and digital-wallet transactions to be linked.
- PAR cannot initiate payments or be reverse-engineered into PANs or payment tokens; it is used only as a reference for connecting transactions.
- A consistent PAR can help merchants maintain customer transaction continuity across processors, channels, payment methods, and card replacement events.

**Tags:** [Architecture](https://yomu.fyi/topic/architecture), [Data Pipelines](https://yomu.fyi/topic/data-pipelines), [Privacy](https://yomu.fyi/topic/privacy)

- Source: [Stripe](https://stripe.dev/blog/tracking-customer-spend-omnichannel-multiprocessor-environment)
- Source URL: https://stripe.dev/blog/tracking-customer-spend-omnichannel-multiprocessor-environment
- Ingested by Yomu: 2026-08-28T08:57:55.268Z

[Read original post](https://stripe.dev/blog/tracking-customer-spend-omnichannel-multiprocessor-environment)