Undoped tin oxide (SnO 2 ) thin films have been deposited in a stagnant point flow chemical vapor deposition reactor from a water/tin tetrachloride mixture. By adding methanol during the deposition process the film electrical properties change significantly: ten times more conductive SnO 2 films are obtained, with remarkably high mobility values of up to 55cm 2 /Vs. The investigations on the morphological and structural properties indicate that the main effect of methanol is the densification of the SnO 2 films, which probably causes the improvement in the electrical properties. In all conditions the nucleation and coalescence phases take place very early in the growth. Below 10nm the films are already very conductive, which is very beneficial to applications that have strict requirements in terms of film transparency.