Fleet mileage tracking in Switzerland: the KPIs that cut leasing costs

Fleet mileage tracking means reading every vehicle's odometer once a month and comparing it with the mileage agreed in its lease. Done regularly, it shows a drift within a few months, early enough to avoid an excess mileage bill when the car goes back.

In Switzerland, mileage also drives service planning, the choice between the 0.9 % private share and a logbook on the salary certificate, and the mileage allowance for private cars used on business. This guide explains the KPIs worth tracking, the Swiss rules behind them, the four ways to collect odometer readings, and a worked example in Swiss francs on 50 vehicles. With Voltaback, the odometer comes straight from the connected car, with no box to install.

Key points in 30 seconds

• What to measure: each vehicle's odometer on a fixed date, the gap to the contract trajectory and the projection at lease end.
• Thresholds: watch above 10 % deviation, act above 15 % (swap vehicles or amend the contract).
• Tax: the 0.9 % private share already covers the commute. With a logbook, private kilometres are declared at CHF 0.75.
• Order of magnitude: in our 50-vehicle example, about CHF 20'000.– of excess mileage avoided per lease cycle and around 60 hours of admin saved each year.

Why kilometres matter so much in a Swiss fleet

A company car costs money mainly through the kilometres it covers. Five budget lines depend directly on the odometer:

• Lease payments and return: kilometres above or below the contract.
• Vehicle allocation: who drives which car, so that every contract balances out.
• Maintenance: services, tyres and brakes are mostly scheduled by distance.
• Salary certificate: choosing between the flat private share and a logbook, and checking mileage allowances.
• Resale value: a high-mileage car is worth less.

Lease excess mileage: how it is charged

A lease fixes a term and a total mileage, for example 48 months and 80,000 km. The monthly rate and residual value follow from that. If the car comes back with more kilometres, the leasing company charges excess kilometres at a contractual rate in centimes (Rappen) per km.

AXA's leasing guide quotes a Eurotax rule of thumb: the residual value divided by 2,000 gives the surcharge in centimes per extra kilometre. With a residual value of CHF 20'000.–, that is 10 centimes per km. The rate in your own contract always prevails.

The reverse does not work in your favour. Unused kilometres are usually not refunded, or only partly. AMAG Leasing's general leasing terms, for example, state that kilometres not driven are not refunded. You have paid for distance nobody drove.

Sources: AXA, frequently asked questions on car leasing ; AMAG Leasing, general leasing terms.

High and low-mileage drivers in the same fleet

The spread is wide. A sales manager based in Zug who covers clients from Zurich to Basel easily exceeds 30,000 km a year. A finance colleague in Geneva who mostly takes the train or tram might only drive 12,000 km.

Give both a 20,000 km-a-year contract and one pays for excess kilometres while the other pays for kilometres never driven. Swapping their cars halfway through often brings both contracts back in line, without renegotiating anything.

Servicing at the right time

Most maintenance deadlines are counted in kilometres. A reading that arrives three months late means a service pushed back without anyone noticing. The alerts that really matter are covered in our guide to fleet maintenance alerts.

Mileage and the salary certificate: what the tax office looks at

Mileage also has a tax side. The reference is the guide to the salary certificate (Wegleitung zum Lohnausweis / Guide d'établissement du certificat de salaire), published by the Federal Tax Administration (ESTV/AFC) and the Swiss Tax Conference (SSK/CSI).

Method 1: the 0.9 % monthly private share

If an employee may use the company car privately, the usual approach is a private share of 0.9 % of the purchase price per month (excluding VAT, minimum CHF 150.– a month), declared in box 2.2 of the salary certificate (Lohnausweis / certificat de salaire). For a leased car, the cash purchase price in the lease contract is used.

The key point for mileage tracking: this private share already includes the commute. Box F is ticked and no commuting deduction can be claimed for that journey (Wegleitung, margin notes 21 to 22). With the flat rate, nobody needs to split private and business kilometres.

Example: a car bought for CHF 50'000.– gives a private share of CHF 450.– a month, or CHF 5'400.– a year on the salary certificate.

Method 2: a logbook with actual private kilometres

Instead of the flat rate, you can declare actual private kilometres × CHF 0.75. This requires a complete logbook (Bordbuch / carnet de bord): every trip with date, destination, purpose and distance, kept as you go, with any later change traceable (SSK, salary certificate FAQ, item 2.2.8). Box F is then not ticked.

The break-even point is simple to work out. In the example above, CHF 5'400.– equals 7,200 private kilometres at CHF 0.75. An employee who drives clearly less privately, commute included, may be better off with a logbook. A heavy private user stays on the flat rate.

A reliable odometer does not replace the logbook: the private versus business split still has to be recorded by the driver, trip by trip. It does provide the start and end readings against which any logbook is checked. How to keep one is explained in our guide to the company car logbook.

Sources: ESTV, Wegleitung zum Lohnausweis 2026 ; SSK, salary certificate FAQ 2026 ; ESTV, salary certificate.

Private car used on business: CHF 0.75 per km

When employees use their own car for work, the employer may pay up to CHF 0.75 per kilometre without declaring the amount on the salary certificate (Wegleitung, margin note 52; SSK model expense regulations (Spesenreglement), item 2.4). The old rate of CHF 0.70 no longer applies.

Here too, the kilometres are the evidence. Without a record of business trips, the allowance is hard to defend in an audit by the cantonal tax administration or the AHV/AVS compensation office. For electric cars specifically, see our article on the private share of an electric company car.

How this compares with other countries

International fleet teams often apply one mileage policy everywhere. The data is the same, but the tax use differs:

Lease excess mileage, by contrast, works the same way across Europe: the earlier a drift is spotted, the cheaper it is to fix.

The KPIs to track

Not every figure is equally useful. These are enough for most fleets:

The last line is often forgotten. A dashboard missing one reading in five gives a false sense of control.

Worked example for one vehicle

A car is leased for 48 months and 80,000 km. After 12 months, the odometer shows 25,000 km.

• Contract trajectory at 12 months: 80,000 × 12 ÷ 48 = 20,000 km.
• Gap: 25,000 ÷ 20,000 = +25 %, above the action threshold.
• Projection: 25,000 ÷ 12 × 48 = 100,000 km, so 20,000 km too many.
• Risk at 10 centimes per km: 20,000 × CHF 0.10 = CHF 2'000.– for this one car.

Spotted at month 12, the gap can be fixed at no cost. Spotted at return, it gets invoiced.

What to do when a vehicle drifts from its allowance

There are four levers. The right one depends on the direction of the gap and the time left.

Most leasing companies will adjust the mileage during the contract if asked early. The sooner you ask, the smaller the monthly change. For renewals, start from the mileage measured on the previous contract: it is the best basis for negotiating with AMAG Leasing, Ayvens, Arval or Alphabet.

How to collect odometer readings: four methods compared

They differ mainly in the time they cost the fleet manager and in how fresh the data is.

Self-declaration is still the most common, but its cost is hidden in reminders and corrections. Fuel cards no longer see electric cars, which mostly charge at home or in the company car park.

A box is reliable, but it is hardware to fit, maintain and remove before the car goes back. The fourth route is the newest: recent cars transmit their mileage through their factory connectivity, and software reads it remotely.

That is what Voltaback telematics does, for petrol, diesel, hybrid and electric cars from more than 48 brands. Older cars can be harder to connect depending on their equipment, and they stay on self-declaration until they are replaced.

Tracking kilometres does not mean tracking trips

An odometer reading is not a location. To manage leases and maintenance, a company only needs totals. The revised Federal Act on Data Protection (nDSG / nLPD) requires that only the data needed for the purpose is processed (proportionality, Art. 6) and that systems are privacy-friendly by default (Art. 7). Article 26 of Ordinance 3 to the Employment Act also prohibits systems intended to monitor employees' behaviour.

Voltaback never passes drivers' locations to the employer. The limits on tracking are covered in our guide to company vehicle geolocation. Sources: nDSG, SR 235.1 ; ArGV 3, SR 822.113.

What mileage tracking pays: example with 50 vehicles

Take a fleet of 50 leased cars across Zurich, Zug, Basel and Geneva, all on 48 months and 80,000 km (20,000 km a year). The excess rate is 10 centimes per km, which by the rule of thumb matches a residual value of about CHF 20'000.–.

After one year, the fleet looks like this:

• 30 cars on trajectory (under 10 % gap).
• 10 high-mileage cars at 25,000 km a year (+25 %).
• 10 low-mileage cars at 14,000 km a year (−30 %).

Without tracking: the bill arrives at return

The high-mileage cars go back at 100,000 km, 20,000 km over each:

10 cars × 20,000 km × CHF 0.10 = CHF 20'000.– in excess mileage.

The low-mileage cars go back at 56,000 km. Payments were made for 80,000 km, and the 24,000 unused kilometres are generally not refunded.

With monthly tracking: a swap at month 24

The gap is visible within a few months. At month 24, high and low-mileage cars are swapped in pairs:

• Car A (high, then low): 50,000 km + 28,000 km = 78,000 km, 2,000 km under the allowance.
• Car B (low, then high): 28,000 km + 50,000 km = 78,000 km, also under.

The CHF 20'000.– disappears, or CHF 5'000.– a year over the lease term. Where swaps are impossible, for instance with personally assigned company cars, an early amendment spreads the extra cost over the remaining payments instead of one final invoice.

Time saved

Assumption to adjust to your organisation: 6 minutes per car per month to chase, enter, check and consolidate a self-declared reading.

50 cars × 6 minutes × 12 months = 3,600 minutes, or 60 hours a year. At a full cost of CHF 55.– an hour, that is about CHF 3'300.–. With automatic readings, only the review of alerts remains.

To model these effects with your own figures, use the telematics savings calculator. The full cost picture is in our analysis of fleet total cost of ownership.

Setting it up in five steps

1. Inventory: plate, first registration, fuel type, lease (term, mileage, excess rate), assigned driver, salary certificate method (0.9 % or logbook).
2. Reading date: one fixed day per month, the same for all cars.
3. Thresholds: 10 % to watch, 15 % to act, 500 km a month as a floor.
4. Responsibilities: who decides a swap, who negotiates with the leasing company, who informs payroll.
5. Employee information: which data is collected (odometer, no location) and why, as the nDSG duty to inform requires.

If your fleet includes leased electric cars, our article on electric company car leasing and tax completes this guide.

Automatic mileage, with no box and no location

Voltaback reads the odometer directly from the connected car, for petrol, diesel, hybrid and electric vehicles. No fitting, no hardware to remove before the lease ends, and no more monthly reminders to drivers.

• Mileage and contracts: up-to-date odometer for every car, gap to trajectory and lease-end projection.
• Alerts: cars above threshold, under-used cars, services coming up.
• Data protection: the company never receives drivers' locations. nDSG compliant, ISO 27001 certified since 2 December 2025.
• Export: monthly export ready to import into your payroll software.

Want to know how much excess mileage your fleet has already built up? Talk to the Voltaback team.