Work out what you really save
An honest, adjustable calculation that accounts for the real costs of sharing.
Your situation
Net annual balance
+693 € per year
- Contribution received from co-drivers +1,000 €
- Extra insurance cost -147 €
- Accelerated depreciation -160 €
In plain terms: your co-drivers cover 33% of the kilometres, so they take on 33% of your 3,000 € of fixed costs, which comes to 1,000 € a year.
Your situation
Net annual saving
+2,500 € per year
- Cost of a personal car avoided +3,980 €
- Your contribution to fixed costs -1,000 €
- Fuel and wear (your share) -480 €
In plain terms: owning your own car would cost roughly 3,980 € a year. By sharing, you pay 1,000 € towards fixed costs and around 480 € in fuel and wear, so you save 2,500 € every year.
Estimates based on 🇫🇷 France
This simulation is an estimate. Car sharing involves many variables (driver profiles, type of vehicle, insurance policy, local tax rules, actual mileage) that can shift the figures noticeably in real life. Treat the result as an order of magnitude, not a definitive calculation.
How this calculator works
Most car-sharing simulators simply divide the costs by the number of people. It is flattering, but wrong: sharing a car does not only spread a bill, it also adds kilometres and wear. This calculator keeps the three effects that genuinely matter.
What you receive
Your fixed costs (insurance, leasing, parking, taxes) are shared in proportion to everyone's kilometres. If you drive 8,000 km, the people close to you drive 4,000 and your annual fixed costs come to 3,000 euros, they take on a third of those costs, or 1,000 euros a year.
What it costs you
Every additional kilometre brings the car closer to its resale and to its next service. On the 4,000 km added by the others, the calculation subtracts around 160 euros of accelerated depreciation. It also deducts an extra insurance cost linked to declaring additional drivers, in the region of 147 euros for two declared drivers.
What you keep
In this example the owner keeps around 693 euros a year. That is less than the 1,000 euros received, and rightly so: the honest number is the one that accounts for wear. It is also a recurring saving, obtained without changing any habits.
On the driver's side the logic is reversed: the calculation starts from the full cost of a personal car, then subtracts the contribution paid to the owner and the fuel actually used. The difference is what the driver avoids spending by not owning a second vehicle.
Where the figures come from
The default values come from the figures published by each country's reference motoring organisation. The calculator detects your region and applies the matching set. Every field stays editable: your own numbers will always give a better answer than a national average.
| Country | Average annual cost | Source |
|---|---|---|
| France | 5,250 EUR a year | Automobile Club Association |
| Switzerland | 11,112 CHF a year | TCS |
| Germany | 6,600 EUR a year | ADAC |
These amounts cover the whole cost of ownership: depreciation, insurance, taxes, servicing, tyres, fuel and parking. That is what explains the gap with the fuel budget people spontaneously think of.
Three concrete situations
Examples calculated with the French reference figures. The amounts are rounded annual orders of magnitude.
One neighbour, occasional use
You drive 12,000 km a year, your neighbour adds 3,000. Your fixed costs are 3,000 euros and you declare one additional driver.
≈ 405 EUR a year
net balance in your favour
An active house share
You drive 6,000 km, your three housemates add 9,000. Your fixed costs are 3,600 euros and all three drivers are declared.
≈ 1,535 EUR a year
net balance in your favour
Giving up your own car
You drive 3,000 km a year with someone else's car instead of running your own. The owner drives 12,000 km and their fixed costs are 3,000 euros.
≈ 2,900 EUR a year
saved by you
The lesson from these three cases is consistent: sharing is worthwhile for the owner, but it is decisive for whoever avoids buying a second car. That is why car sharing between people close to each other works best when one person owns the vehicle and the others do not need it full time.
Frequently asked questions about savings
How much can you really save by sharing your car?
For an owner, the net balance (costs reimbursed minus additional wear) often lands somewhere between 400 and 1,500 euros a year, depending on how many kilometres the other drivers add and on your fixed costs. For someone who gives up owning a car, the saving is far larger, usually between 2,500 and 3,500 euros a year, because they avoid the insurance, depreciation, parking and taxes of a second vehicle.
Why does the owner save less than the guest driver?
Because the two of them do not start from the same place. The owner already has the car: they recover a contribution to costs they used to carry alone, but they also take on extra wear. The guest driver avoids the full cost of a vehicle they never have to buy. Sharing does not create money, it stops the same money being spent twice.
Is the contribution you receive taxable income?
When sharing between people close to each other, this is not rent but a reimbursement of costs actually incurred. As long as the contribution stays at or below the vehicle's costs, it is not a profit. The rules vary by country and by situation: check with your tax authority if you share at scale or if you charge more than your costs.
Does the calculation account for the extra wear on the vehicle?
Yes. That is what sets this calculator apart from simply dividing the bill. Every kilometre another driver adds brings the vehicle closer to its resale and to its next service. The calculation therefore subtracts accelerated depreciation from the owner's balance, along with an extra insurance cost linked to declaring additional drivers.
Do you have to declare the other drivers to your insurer?
An occasional driver is usually covered by the owner's policy, but a regular driver most often has to be declared, and a young driver almost always triggers a surcharge. The conditions vary by insurer and by country. Check your policy before sharing: it is the only genuinely necessary piece of paperwork.
Do these figures apply to my country?
The calculator carries reference figures for three countries: Switzerland (TCS), France (Automobile Club Association) and Germany (ADAC). It switches automatically to the Swiss figures if you browse from Switzerland and to the German ones from Germany, and otherwise falls back on the French figures. Elsewhere the orders of magnitude are close, and the manual fixed-cost setting lets you match your real situation.
Going further
How Co-oto splits the costs
Price per kilometre, price per hour, fixed costs and balances: the detail of the calculation, with worked examples.
How it works
The whole flow, from creating the circle to settling up between members.
How much to charge per kilometre
The official ceilings, the real costs and the line beyond which it stops being cost sharing.
Convincing the people around you
Six concrete arguments to share with the person you want to bring into the project.