Mellow vs Personio: which is better for UK employers?
Personio is a well-funded European HR platform that has grown significantly in the UK market. If you are evaluating HR software and Personio has appeared on your shortlist, the comparison worth making is whether a platform built for the European mid-market serves UK-specific payroll and compliance requirements as well as one built from the ground up for UK employment law.
Payroll
With Mellow, UK payroll is included in the published Professional tier price — PAYE, NI, RTI submissions, SMP, SPP, SSP, student loan plans — as a native part of the platform, in the same subscription as HR. Personio offers UK payroll capability too, but for UK employers who want a single published price covering both HR and payroll without a separate line item, that packaging difference matters.
Specialist agents vs a general assistant
Personio ships an AI Assistant and recruiting agent that work across the product. Mellow takes a different approach: specialist domain agents, including a People Coach and compliance-focused assistants grounded in UK employment law, rather than a single general assistant. For UK employers, agents that reason in the specific context of ERA 2025 and your own workforce data are the differentiator.
ERA 2025 compliance
Personio is a German company with a product built around European employment law structures. UK-specific compliance obligations — the Employment Rights Act 2025 changes, ACAS Code integration, right to work checks, DBS tracking — sit alongside that broader European foundation. Mellow was built specifically for UK employment law, including the Employment Rights Act 2025 provisions, from the outset, so that accuracy is the core rather than a regional module.
Right to work and DBS
Mellow tracks right to work check dates, document expiry, and DBS renewal reminders natively. These are standard features, not bolt-ons, because they are standard UK requirements.
Pricing
Personio operates on a per-employee-per-month model with pricing that scales with the number of modules. For a UK business of 100 to 250 employees, Personio's all-in pricing typically sits materially above Mellow's Professional tier. Exact pricing depends on configuration and negotiation, but the headline difference is meaningful.
What Personio does well
Personio is a mature, well-resourced platform with strong applicant tracking, a polished interface, and a solid European customer base. For businesses with significant operations in Germany, Austria, Switzerland, or Spain, Personio's multi-country support is a genuine strength. For a UK-only business, that strength is less relevant.
The honest summary
If you are a UK employer with 50 to 500 employees, you want a platform where UK PAYE payroll, HMRC RTI submissions, ERA 2025 compliance, and right to work tracking are part of the published price and built into the core — backed by specialist agents that reason in UK terms. Mellow was built for exactly that requirement. Personio is a strong European platform, but its centre of gravity is the wider European mid-market.
See our HR software buyer's guide for the criteria to evaluate any HR platform, and best HR software for UK SMEs in 2026 for the broader market landscape.
[Compare Mellow plans →](https://mellowhr.com/pricing)