A method for fabricating protective seals or "boots" for electric switches, such as push button and toggle switches, is described. In place of traditional rubber molding techniques, the seals are made by thermoforming a plastic film, preferably polyurethane, over a mold containing the nut portion of the seal and pins configured for a suitable shape for toggle or push button switches. Inexpensive stamped, threaded nuts can be employed, and this, together with reduced tooling costs and the efficiency of the method, produce extremely economical electric switch seals. The seals themselves offer unique benefits in that the thin, yet tough, plastic film does not interfere with the functioning of the switches, while providing prolonged service life under difficult conditions. Utilizing clear urethane film, the resultant seals provide clear viewing of the functioning of the switch within.