Tungsten oxide (WO3) thin films are well established materials for electrochromics. Among the various growth techniques adopted, reactive DC Magnetron sputtering has several advantages; the technique also is industrially viable. Argon is the sputter gas used in all the sputtering techniques mainly because of the cost and availability. Sputtering being plasma assisted and momentum transfer process, any sputter gas other than argon, is anticipated to bring significant changes not only in the process of creation of plasma and sputter process but also in the growth of the thin film in terms of the microstructure and consequently the physical properties. In the present investigation, the electro-chromic properties of tungsten oxide (WO3) thin films prepared (on glass and Lexan substrates, lexan is a polycarbonate)by reactive DC Magnetron sputtering using neon as the sputter gas have been studied. The deposition rates on glass and lexan substrates of WO3 thin films with neon and argon as sputter gases are 6.2 nm/min and 13.3 nm/min respectively. The electrochromic properties (with 1.0 Molar Lithium sulphate as the electrolyte) show a remarkable coloration efficiency (and excellent stability over cyclic operations) for neon sputtered WO3 thin films both on glass (136.9 cm2/C) and lexan (187.9 cm2/C) substrates; the corresponding values for the argon as sputter gas are: on glass substrate 90.4 cm2/C and on lexan substrate 143.9 cm2/C.