Take the A11 from Paris to Rennes - 3 h. Then from Rennes take the expressway RN 137 to St-Malo in 35 mn. Or take the A13 from Paris via Caen by the A84 in 3h30
From England & Jersey
By Train
By Plane
The TGV high-speed train leaves Paris Montparnasse station and arrives direct in Saint-Malo 3 hours later.