Five Banks, a Fifth of the RevenueNarrow moat

Mastercard (MA) — moat facet

Mastercard's top five banks bring in $6.9 billion a year and have been about a fifth of its revenue since 2017.

The customer concentration disclosure in Mastercard's 10-K has two halves. The reassuring half: it did not have any individual customer that generated greater than 10% of net revenue in 2025, 2024 or 20231. The other half: net revenue from its five largest customers was approximately $6.9 billion in 2025, or 21%2.

Five largest customers, net revenue ($bn)2.920173.420204.720225.620236.320246.92025Mastercard Forms 10-K FY2017-FY2025
Growing with Mastercard, not faster.

That share has been remarkably steady. It was about $2.9 billion or 23% in 20173, $3.4 billion or 22% in 20204, $4.7 billion or 21% in 20225, and $6.3 billion or 22% in 20246. The five banks have grown with Mastercard, not faster than it.

The customers are not named. That matters less than the fact that each is large enough to run a tender between the two networks, and that the rebates Mastercard pays are set in exactly such negotiations. Rebates grew 16% in 2025, faster than the payment network's 12%7.

A bank merger among the top customers would raise the share without any change in Mastercard's business, and give the merged bank more leverage.

Mastercard's filing names the risk directly: loss of substantial business from significant customers and consolidation amongst its customers are both on its list of factors that could affect results8. The five-customer share has been stable partly because Mastercard's revenue base has broadened into services and into faster-growing regions; the same five banks bringing in $6.9 billion9 represent a smaller share of a company that sells more to everyone else. The concentration is steady, not falling.

The 21-23% band is the thing to watch. A move above 25% would say consolidation among Mastercard's customers is concentrating the purchasing power that sets its rebates.

Moat trajectory: Holding steady

The share has stayed between 21% and 23% since 2017.

The number that tests this moat
Reported
Net revenue from the five largest customers
About $6.9bn (2025), from $6.3bn in 2024

The dollars the top banks bring; growth well above net revenue growth would mean concentration is rising.

Source: Mastercard Form 10-K, FY2025 ↗
References
  1. ReportedThe reassuring half: it did not have any individual customer that generated greater than 10% of net revenue in 2025, 2024 or 2023.
    Mastercard Form 10-K for fiscal 2025 - Item 7 MD&A: net revenue by category, key metrics, rebates, geography and the five largest customers. — FY2025 · publ. 11 February 2026 · source ↗
  2. ReportedThe other half: net revenue from its five largest customers was approximately $6.9 billion in 2025, or 21%.
    Mastercard Form 10-K for fiscal 2025 - Item 7 MD&A: net revenue by category, key metrics, rebates, geography and the five largest customers. — FY2025 · publ. 11 February 2026 · source ↗
  3. ReportedIt was about $2.9 billion or 23% in 2017, $3.4 billion or 22% in 2020, $4.7 billion or 21% in 2022, and $6.3 billion or 22% in 2024.
    Mastercard Form 10-K for fiscal 2017 - gross revenue and rebates for 2015-2017, net income and EPS, headcount and the 2017 tax charge. — FY2017 · publ. February 2018 · source ↗
  4. ReportedIt was about $2.9 billion or 23% in 2017, $3.4 billion or 22% in 2020, $4.7 billion or 21% in 2022, and $6.3 billion or 22% in 2024.
    Mastercard Form 10-K for fiscal 2020 - gross revenue and rebates for 2018-2020, the 2020 decline, the Finicity acquisition and the European Commission fine. — FY2020 · publ. February 2021 · source ↗
  5. ReportedIt was about $2.9 billion or 23% in 2017, $3.4 billion or 22% in 2020, $4.7 billion or 21% in 2022, and $6.3 billion or 22% in 2024.
    Mastercard Form 10-K for fiscal 2022 - key metrics and rebates for 2020-2022, the Ekata and Dynamic Yield acquisitions and the five largest customers. — FY2022 · publ. February 2023 · source ↗
  6. ReportedIt was about $2.9 billion or 23% in 2017, $3.4 billion or 22% in 2020, $4.7 billion or 21% in 2022, and $6.3 billion or 22% in 2024.
    Mastercard Form 10-K for fiscal 2024 - net revenue categories recast for 2022-2024, rebates of $17,629 million, the five largest customers and the Recorded Future acquisition. — FY2024 · publ. February 2025 · source ↗
  7. ReportedRebates grew 16% in 2025, faster than the payment network's 12%.
    Mastercard Form 10-K for fiscal 2025 - Item 7 MD&A: net revenue by category, key metrics, rebates, geography and the five largest customers. — FY2025 · publ. 11 February 2026 · source ↗
  8. ReportedMastercard's filing names the risk directly: loss of substantial business from significant customers and consolidation amongst its customers are both on its list of factors that could affect results.
    Mastercard fourth-quarter and full-year 2025 results release, Form 8-K exhibit 99.1 - statements, cash flow and operating metrics. — FY2025 · publ. 29 January 2026 · source ↗
  9. ReportedThe five-customer share has been stable partly because Mastercard's revenue base has broadened into services and into faster-growing regions; the same five banks bringing in $6.9 billion represent a smaller share of a company that sells more to everyone else.
    Mastercard Form 10-K for fiscal 2025 - Item 7 MD&A: value-added services and solutions. — FY2025 · publ. 11 February 2026 · source ↗
Sources
Generated September 25, 2026