MOVE / IDF ↗
Mobility handbook · Île-de-France · September 2026
Mobility decision desk / 01

Buy access first.
Own only what earns its place.

Compare a mobility portfolio—not just vehicles. Every option is translated into monthly economic cost, employer support, capital tied up, residual value and operational limits for an Île-de-France user.

Lowest modeled economic cost

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The cheapest mode may not cover every trip. A resilient answer is often a low-cost backbone plus occasional capacity.
Mobility decision desk / 02

Compare access, subscriptions and assets

Click for the finance and accounting cut

Mobility decision desk / 03

One accounting language across every mode

Monthly cash paid is not always economic cost. Assets depreciate and retain value; subscriptions may receive employer support; pay-per-use mobility scales with usage.

SolutionAccounting typeFixed costVariable costCapital / residualEmployer treatmentBest use
Mobility decision desk / 04

Build a portfolio, not a single answer

Daily backboneNavigo, Liberté+ or a bicycle covers predictable movement at low marginal cost.
Capacity layerAdd rental, carshare or taxi only for journeys needing cargo, motorway range, late-night availability or passengers.
Resilience layerKeep two usable modes so disruption, weather, punctures or rental availability do not cancel the trip.
Ownership gateOwn only when avoided rentals, time saved and availability exceed depreciation, capital, parking and maintenance.
Mobility decision desk / 05

Break-even signals

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Round-trip threshold where supported Navigo beats Liberté+.

—Owned small-car premium versus Navigo + rental.
—Bike purchase payback versus supported Navigo, before valuing time or weather.
Accounting ruleLoan principal builds an asset. Count depreciation and interest or opportunity cost—never principal twice.
Problem branch / Vehicle ownership

When access becomes an owned vehicle

Choose the vehicle used in the main comparison, edit CAPEX for every category, and model the correct energy carrier. The combustion car can run on petrol or diesel; the recent vehicle can be modeled as a full EV or hybrid.

Editable petrol, diesel and electricity prices from the main assumptions panel.
Vehicle cost = CAPEX depreciation + opportunity cost on average capital + insurance + parking + maintenance/tax + carrier-specific energy − realistic platform offset. Energy cost = annual km × consumption × unit price.

Current reference points

Navigo is modeled at €90.80/month in 2026, reduced by your employer percentage. Liberté+ uses €1.82 per leg as a planning average between published rail/metro and bus/tram fares. Vélib uses €9.30 V-Max plus an €8 usage buffer; Véligo uses €40/month. Bike, car, resale and maintenance figures are planning assumptions.