The morphological, structural, electrical and optical properties of F:SnO2 (FTO) films are studied. The films were grown using the chemical spray pyrolysis technique from solutions containing F/Sn in the range 0-80 wt% . XRD measurements showed that the films are polycrystalline with the Rutile structure and with mixed preferred orientation along the (200) and (110) planes. The classical theory of free carrier absorption is used to establish a relation between the near IR absorption coefficient and the electron concentration in the films. Using this relation, it is shown that the electron concentration n increases monotonically with the increase of the F/Sn ratio in the solution. The dependence of the electron concentration n and the Hall mobility μH on the annealing temperature TA confirms that ionized impurity scattering is the mechanism limiting the carriers mobility in the films and that significant increase in the concentration of compensating acceptors takes place above TA =550 C. The variation of the optical energy gap Eg with annealing temperature is interpreted semi-quantitatively taking into account the combined effect of the Moss-Burstein shift and the Urbach tailing. Moreover, the variation of Eg with the refractive index nr (determined using the experimental reflectivity) is found to be in agreement with the general relation Eg ∝ (n2-1)-0.5 followed by several other semiconductors. The packing factor show a minimum at TA = 550 oC which agrees with the behavior of the grain size with TA determined from both XRD and AFM measurements.