Quick answer: As a rule of thumb, businesses with fewer than about 25 to 30 employees usually get better value from an outsourced HR consultant than from hiring in-house. A consultant gives you broad expertise across employment law, contracts and tricky cases for a fraction of a salary. Once you have constant daily HR work, or roughly 30-plus staff, a dedicated in-house hire can start to pay for itself. Many growing SMEs use both: a consultant for expertise and an in-house administrator for day-to-day tasks.
Side by side
| Factor | Outsourced HR consultant | In-house HR hire |
|---|---|---|
| Typical cost | From about £249/month | HR Advisor £30k to £38k; HR Manager £40k to £55k+ plus on-costs |
| Expertise | Broad, drawn from many businesses and cases | Deep on your business, narrower on edge cases |
| Availability | Working hours, scheduled and urgent | Full time, on site |
| Best for | Under ~30 staff, or variable HR needs | 30+ staff, or high daily HR volume |
| Risk cover | Employment-law current and tribunal-aware | Depends on the individual’s experience |
| Flexibility | Scale up or down, no employment cost | Fixed salary and overhead |
How to decide
- Choose a consultant if you are under about 30 staff, need senior expertise occasionally, and want to control cost.
- Choose in-house if HR has become a daily, full-time job.
- Consider a hybrid as you grow: your team handles admin, a consultant handles expertise and risk.
Frequently asked questions
At what size should I hire in-house HR?
Often around 30 to 50 employees, but it depends on how much HR activity you have, not headcount alone.
Can a consultant work alongside my office manager?
Yes. That hybrid is common: your team handles day-to-day admin while the consultant handles expertise and risk.
What does an outsourced HR consultant actually do?
Contracts and policies, compliance, disciplinaries and grievances, redundancies, performance management, and day-to-day advice.