Mellow vs CharlieHR
CharlieHR for grown-ups
Simple HR for small teams. Serious HR for growing ones.
Assistants that take action
Mellow’s agents generate contracts, run payroll estimates, start compliance workflows, and produce audit-ready documents — not just answer questions.
CharlieHR
UK-built, startup-focused
10–100 employees
From £5+ PEPM (estimated)
Mellow
UK-built, UK-first
10–500+ employees
From £4/employee/month
Things to consider
- ✗Built for startups and small teams
- ✗No payroll processing
- ✗No IR35 support
Feature comparison
| Feature | Mellow | CharlieHR |
|---|---|---|
| Core HR | ||
| Employee directory | ||
| Holiday tracking | ||
| Probation tracking | ||
| Document storage | ||
| Onboarding workflows | ||
| Payroll | ||
| UK payroll processing Full PAYE/NI calculation — CharlieHR sends you to Xero | No native payroll — Xero integration only | |
| Native UK payroll + ready-to-file output PAYE, NI & statutory to the penny + BACS; produces a ready-to-file output (filing pack) | No payroll capability — no RTI | |
| Compliance | ||
| ERA 2025 compliance | ||
| Bradford Factor | ||
| IR35 determination | ||
| AI | ||
| AI assistants AI assistants included per tier, up to a People Coach | ||
| AI manager coaching (People Coach) In-product coaching for conflict & team issues | Human advice line (Charlie Advice, £179+/mo), not AI coaching | |
| People | ||
| Adjustments Passport Living per-employee record of agreed workplace adjustments, per-country legislation, AI-drafted wording | No equivalent | |
| Team-health index from operational signals Fused index from workload, ER, absence & recognition | Pulse & 360 surveys — not a fused operational-signal index | |
| Scale | ||
| Workforce planning | ||
| Tribunal risk scoring | ||
Our take
CharlieHR is a well-built HR tool that small startup teams genuinely value. As headcount grows past 50, the requirements shift — IR35 determinations, ERA 2025 compliance, tribunal risk assessments come into scope, and those need a different level of depth. On payroll: CharlieHR routes you to Xero rather than calculating it natively. Mellow calculates the full picture — PAYE, NI, statutory deductions, BACS files — and prepares a ready-to-file output. Mellow does the calculation; the filing itself stays with you.
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