Automatic Data Processing, Inc. (ADP)

How it makes money

Employer Services earns recurring fees for processing payroll and running HR software, priced mostly per employee. PEO Services bills clients for the wages, benefits and administrative fee of the worksite employees it co-employs, which makes its reported revenue much larger relative to its actual profit. A third, smaller and more volatile source is interest earned on client payroll funds ADP holds briefly before paying employees — $1.19 billion in fiscal 2025, up 16% as interest rates stayed elevated.

Revenue by segment

Payroll and HR software become deeply integrated with a client's time-tracking, benefits and tax-compliance processes, and switching providers risks payroll errors and compliance penalties, so clients rarely move once onboarded — fiscal 2025 client revenue retention reached 92.1%. Decades of scale also let ADP spread compliance expertise across all fifty US states and dozens of countries in a way smaller rivals struggle to match.

Employer Services revenue scales with the number of employees processed and wage growth, so it softens when hiring slows and companies shed staff in a downturn, but does not collapse the way a purely discretionary business would. The interest income on client funds is a separate, purely rate-driven swing factor: it rose with elevated interest rates in recent years and would fall if rates come down.

Key risks

• Interest-rate sensitivity of float income — Interest earned on client funds reached $1.19 billion in fiscal 2025, up 16% as rates stayed elevated. A meaningful decline in interest rates would remove a tailwind that has boosted recent results.
• Custody of client funds — ADP temporarily holds very large sums of client payroll money before disbursing it to employees, which creates operational, regulatory and reputational exposure if those funds are mismanaged or misappropriated.
• Competition from newer HCM entrants — Cloud-native payroll and HR platforms compete on price and integration simplicity, particularly for smaller employers, pressuring ADP to keep modernizing legacy systems built up over decades.
• Co-employment legal exposure — As the legal employer of record for PEO clients' worksite employees, ADP takes on joint-employer liability under labour and tax law across many jurisdictions, exposure a pure payroll processor would not have.