A failed mid-level hire now costs UK businesses an average of £132,000, according to REC's 2025/26 update, and that figure is calculated before the Employment Rights Act's changes to unfair dismissal even take effect. For SMEs, the real damage is rarely the headline number, it's what happens to a small team while the mistake is still being figured out.
Where the real cost sits
The average cost to hire in the UK is around £6,125 per role, according to CIPD, before salary or onboarding are even factored in. That's the cost of getting someone in the door. The far bigger number comes from what happens if the hire doesn't work out:
- REC's 2025/26 data puts the average cost of a failed mid-level hire at roughly £132,000, once recruitment, onboarding, lost productivity and replacement costs are all accounted for.
- Replacing an employee more broadly costs a UK business an average of £30,614, according to Oxford Economics and Unum research, rising well beyond that for specialist or senior roles.
- In small teams specifically, a single underperforming hire can reduce departmental productivity by around 30%, since colleagues absorb the gap while the issue is identified and addressed.
- It typically takes 12 weeks or more for a new hire to become fully productive, which means the true cost of a mismatch is rarely visible for months after the hire is made.
Why this number is about to get worse, not better
Most of these figures assume a business can identify a bad hire and act on it reasonably quickly. That assumption is getting shakier. Under the Employment Rights Act 2025, the qualifying period for unfair dismissal drops from two years to six months from 1 January 2027, with the compensation cap removed entirely, changes we've broken down in full in our Employment Rights Act explainer. The upshot is straightforward: businesses will have far less time to work out whether a hire is genuinely right, and far more financial exposure if they get the process of managing that wrong.
For a small team, this compounds an already painful problem. Sunk cost thinking, "we've already invested three months in this, let's give it more time", keeps underperforming hires in place longer than they should be, which is exactly the pattern that turns a £6,000 hiring cost into a six-figure mistake.
What this means for how you hire
The instinct is often to slow down and interview more thoroughly. That helps, but it doesn't solve the underlying problem, which is that most of the signal on whether a hire will actually work out only shows up after they start, not during the interview. That's why a structured probation process, with real milestones and documented check-ins rather than a vague settling-in period, matters more than one more round of interviews.
It's also why vetting before a candidate ever reaches your desk carries so much weight. A model that filters for fit and reliability before you commit to a contract removes a large share of this risk before it ever becomes your problem to manage. If you want to see how that works in practice, our FAQ on the hiring and employment process covers exactly what gets checked before a candidate is put in front of you.
FAQ
How much does a bad hire actually cost a UK business? REC's 2025/26 data puts the average cost of a failed mid-level hire at around £132,000, factoring in recruitment, onboarding, lost productivity and replacement costs.
Is the cost of a bad hire higher for small businesses? Proportionally, yes. A single underperforming hire in a small team can reduce departmental productivity by around 30%, since there's less capacity elsewhere to absorb the gap.
How long does it take to recognise a bad hire? Recognition often lags well behind onboarding, with new hires typically taking 12 weeks or more to become fully productive, meaning issues can go unaddressed for months.
Will the Employment Rights Act make bad hires more expensive? It's likely to increase the cost of getting a dismissal wrong, since the unfair dismissal qualifying period is dropping to six months from January 2027, with the compensation cap removed.
What's the most effective way to reduce the risk of a bad hire? Strong upfront vetting combined with a genuine, milestone-based probation process, rather than relying on interviews alone, catches most mismatches earlier and at lower cost.
Sources
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