Grey fleet policy: Template and a practical guide for UK employers 

As long as only a few employees occasionally claim mileage, grey fleet management can feel manageable. But as your organisation grows, informal processes quickly become unclear, inconsistent, and harder to oversee.
A grey fleet policy isn’t just about compliance. It’s about defining ownership, setting expectations, and putting structure in place before small gaps turn into operational risk.

This guide is for UK HR, operations, and finance teams responsible for managing business travel who want a clear, workable grey fleet policy that people actually follow.

Do you need a grey fleet policy?

Short answer: yes - if anyone drives their own vehicle for work.

From a legal perspective, your duty of care starts the moment one employee drives for business. The Health & Safety at Work Act applies whether the vehicle is company-owned or privately owned.

From a practical perspective, a policy becomes essential as soon as:

• More than a handful of employees claim mileage
• Managers need to approve mileage regularly
• You reimburse travel through payroll or expenses

At that point, managing a grey fleet shifts from occasional admin to an ongoing process that requires clarity and consistency.

There are two important thresholds to be aware of:

1. The legal threshold (5+ employees)

If your organisation employs five or more people, UK law requires you to have a written health and safety policy, and since driving is one of the highest-risk work activities, that policy must cover driving for work, including grey fleet.

2. The operational threshold (~10 drivers)

Even with fewer employees, once 10 or more people drive for work, informal processes stop scaling. This is where:

• Document checks get missed
• Approvals become trust-based
• No one is quite sure who owns what

A written policy turns assumptions into clarity.

Our own research with teams managing employee mileage highlights a common challenge as organisations grow:

“As teams grow, informal mileage processes break down — not due to bad intent, but because checks and oversight don’t scale.”

Source: Sales & Onboarding Call Analysis, 2025

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What does a good grey fleet policy include?

The most effective grey fleet policies are simple and structured. They create clarity around three areas: the vehicle, the driver, and the journey (which you might remember from your grey fleet risk assessment).

• When it comes to the vehicle, the policy should define what “safe and suitable for work” actually means. It should clarify that the vehicle must be roadworthy, properly insured for business use, maintained, and appropriate for work-related travel. Setting minimum standards removes ambiguity and prevents assumptions on both sides.
• When it comes to the driver, the policy should make responsibilities explicit. Employees must hold a valid licence, declare relevant changes, and understand the standards expected when driving for work. For managers, this removes guesswork. For employees, it removes uncertainty.
• The third pillar is the journey itself. A strong policy helps employees pause and consider whether a personal vehicle is the right option in the first place. Encouraging conscious travel decisions can reduce costs, risk, and emissions, but only if expectations are clear and easy to apply in real situations.

How to implement a grey fleet policy (and make it stick)

Creating a policy is one thing. Embedding it into everyday operations is another.

Successful organisations make expectations visible. The policy forms part of onboarding, is referenced in internal systems, and is easy to access. It does not disappear into folders that no one revisits.

They also make it easy to do the right thing. Clear guidance, consistent mileage submission processes, and simple reporting structures remove friction. When expectations are straightforward and supported by the right tools, compliance becomes routine rather than reactive.

Finally, they review their approach regularly. As teams grow and travel patterns change, your fleet setup and internal processes may need to evolve. Reviewing mileage data, vehicle mix, and ownership responsibilities at least annually ensures your policy continues to reflect reality rather than assumptions.

How to enforce the policy without creating admin overhead

Enforcement does not have to mean heavy monitoring. In practice, it means putting guardrails in place so the right actions happen by default.

This can include:

• Only reimbursing mileage when the required documents are valid
• Setting reminders for expiring licences or insurance
• Standardising trip reporting through one consistent system

When processes are structured and transparent, oversight becomes easier without adding unnecessary complexity.

A grey fleet policy, when implemented well, is less about control and more about clarity. It defines who owns what, reduces friction as you scale, and ensures that growth does not quietly increase risk.

Get a free downloadable grey fleet policy template (PDF, Google Doc)

To make this easy to implement, we’ve created a free, customisable grey fleet policy template you can adapt to your organisation. It’s intended as a general reference and does not constitute legal advice or a legal agreement.

It includes:

• A ready-to-use policy structure
• Practical examples
• Implementation tips
• Review and enforcement guidance

👉 Download the grey fleet policy template

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