How to implement the mobility budget: the complete step-by-step guide for employers

Because implementing a mobility budget doesn't happen in an afternoon. It requires a policy, a TCO calculation, legal documents and a management tool. Those who start in December 2026 will have a problem.

This step-by-step guide walks you through the entire process. From initial inventory to daily management. Concrete, complete and ready to apply.

Step 1: map your current fleet and eligible employees

Before putting anything on paper, you need to know who's entitled to a mobility budget and what it costs.

Create an overview of all employees with a company car or whose job function entitles them to one. That's the group that can opt in. Important: the mobility budget doesn't only apply to those currently driving a company car, but also to those eligible based on their job category.

Per employee or per job category, map the current vehicle: make, model, lease cost, fuel consumption, CO2 emissions, insurance costs and remaining lease duration.

This overview is the foundation for everything that follows. Without this data, you can't calculate a TCO or determine a budget.

What you can do tomorrow: ask your fleet manager or leasing company for an export of all running contracts, including all cost items.

Step 2: calculate the TCO per employee or job category

The mobility budget is based on the Total Cost of Ownership (TCO) of the company car the employee exchanges. Not the catalogue price. Not the lease cost. The total annual gross cost for you as employer.

That TCO includes:

• Leasing or depreciation
• Fuel
• Insurance
• Maintenance
• Tyres
• Car wash
• Parking
• Non-deductible VAT
• Tax on disallowed expenses
• CO2 solidarity contribution

Since 2024, you must choose between two official calculation formulas.

The actual cost formula

Uses the effective costs of the past four years. Ideal if you have detailed data per employee.

The lump sum value formula

Works with fixed and variable components based on lease or purchase cost and commuting kilometres. Simpler, and easy to combine with reference vehicles per job category.

Whichever method you choose: you must apply it consistently for at least three years for all employees. One method, no exceptions.

The mobility budget must amount to at least €3,233 per year in 2026 and cannot exceed 20% of gross annual salary, with an absolute ceiling of €17,244.

What you can do tomorrow: download the Mbrella TCO calculator and run a first calculation per job category. You'll immediately know what budgets you're working with.

Step 3: draft a mobility budget policy

The law requires a written mobility policy before employees can opt in. No policy, no mobility budget.

In that policy, you define:

Who is eligible?

You define the job categories and entry conditions. You may determine that employees can only opt in when their current lease contract expires. You may also differentiate between categories, as long as it's objective and transparent.

What do you offer in pillar 1?

Since 2026, every car in pillar 1 must be fully electric (zero CO2 emissions). Determine which models or budget categories you offer.

What do you offer in pillar 2?

This is where the flexibility lies. You must offer at least one option in pillar 2. Options include:

• Public transport
• Bike leasing
• Shared mobility
• Carpooling
• Housing costs (rent or mortgage, under certain conditions)

The broader the offer, the more attractive for employees.

How does pillar 3 work?

The remaining balance after pillars 1 and 2 can be paid out in cash to the employee. A special employee contribution of 38.07% applies.

What are the rules?

Think about when an employee can opt in, how they apply, what supporting documents are needed for pillar 2, and how the annual settlement works.

A strong policy protects you during an NSSO audit and gives employees clarity.

What you can do tomorrow: download the free Mbrella mobility budget policy template. Legally validated and ready for implementation.

Step 4: prepare the individual documentation

On top of the company-wide policy, you need to draft an individual addendum to the employment contract for each employee who opts in. This addendum contains the exact mobility budget amount, applicable conditions and chosen pillars.

The process works like this:

• The employee submits a written request, by email or via a form. This request is legally required.
• Based on that request, you draft the addendum. Both parties sign. Only then can the employee use the budget.
• If an employee wants to include housing costs in pillar 2, you also need a declaration on honour. The employee confirms that the property meets the conditions: either within 10 km of the workplace, or at least 60% remote work.

Without this documentation, you risk the NSSO reclassifying the mobility budget as ordinary taxable salary.

What you can do tomorrow: identify which employees are first in line (lease contract expiring) and prepare their file.

Step 5: choose the right partners and tools

Managing a mobility budget with spreadsheets works until your fifth employee opts in. After that, it becomes unmanageable.

You need two types of partners:

• A leasing company for pillar 1. They provide the electric company car. Compare the best leasing companies for SMEs here and see which one fits the mobility budget best.
• A management platform for the full mobility budget. This platform centralises all expenses across the three pillars, syncs with your social secretariat for payroll processing, and gives employees real-time insight into their balance. That's exactly what Mbrella does. See how it works or book a demo.

Also check whether your management tool supports the legal reporting requirements. The NSSO can request how the budget was spent per employee.

What you can do tomorrow: request quotes from two or three management platforms and test their user-friendliness.

Step 6: communicate clearly to your employees

This is where many companies stumble. The policy is perfect, the tools are chosen, but nobody understands how it works.

The mobility budget is new and complex for most employees. If you don't explain it well, people cling to their company car out of uncertainty.

Organise an info session with concrete examples. Show what an employee in a specific job category can actually do with the budget:

• How much is left if they choose a smaller car?
• What can they spend on a bike or train subscription?
• What gets paid out net in pillar 3?

These mobility budget examples in practice can help make it tangible.

What you can do tomorrow: schedule a date for an internal info session and prepare a Q&A document with the most common questions.

Step 7: launch, monitor and adjust

After launch, the real work begins. Track how many employees opt in, how they spend their budget and where questions or bottlenecks emerge.

Check each quarter whether your CREG rates for home charging are still current. These are updated quarterly and determine the maximum reimbursement amount for employees who charge at home. Read more about current CREG rates.

Evaluate your policy after six months:

• Are the pillar 2 options broad enough?
• Are enough employees opting in?
• Are there unexpected administrative bottlenecks?

A mobility budget is not a one-off project. It's a living system that evolves with your organisation.

The timeline: when to do what?

• Now (Q2 2026): fleet inventory, TCO calculation, draft policy, select partners.
• Q3 2026: prepare documentation per employee, roll out communication plan, start pilot group.
• Q4 2026: prepare full launch, test integration with social secretariat.
• 1 January 2027: mandatory offer for companies with 50+ employees.
• 1 January 2028: mandatory offer for companies with 15 to 49 employees.

Companies with fewer than 15 employees are currently exempt.

Start today

The mobility budget is becoming mandatory. The question isn't whether you need to implement it, but how prepared you'll be when the time comes. Those who start now have time to test, adjust and bring employees on board. Those who wait will have to do everything at once.

Download the free mobility budget e-book or book a demo with Mbrella and discover how other companies are doing it.

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For a more complete overview and understanding on the legal mobility budget, its perks and implementation, download our (free) e-book