The most affordable transport options from Charles de Gaulle Airport (CDG) to Paris are the RER B train and bus services like Roissybus, Bus 350, and 351. The RER B train is generally the cheapest option, offering direct connections to various stations in Paris.

The absolute cheapest way to get from Charles de Gaulle (CDG) Airport to central Paris in 2026 is by taking a local bus, specifically the RATP lines 350 or 351. These buses cost only a few euros (approx. €2.15 if using a T+ ticket or Navigo Easy card) and take you directly to major hubs like Gare du Nord or Nation. However, they are significantly slower than other options, often taking 60 to 90 minutes in traffic. A slightly more expensive but faster "budget" option is the RER B train, which costs about €11.80 and reaches central Paris (Châtelet-Les Halles) in roughly 35 minutes. It is important to note that as of March 1, 2026, the traditional Roissybus service is being replaced by the new Express 9517 bus line, which aims to provide a more streamlined connection to various Metro and RER stations. For those on a very tight budget, the local bus remains the champion of price, even if it requires more patience and navigating with luggage on a standard commuter vehicle.