Unplasticised poly(vinyl chloride) (uPVC) films have been tested using the essential work of fracture (EWF) method. Influence of loading rate and film thickness on the tensile properties and work of fracture parameters was evaluated. In addition, energy partition analyses were carried out applying two different approaches ("yielding" and "initiation"), which differ in the treatment of the stored elastic energy. Results showed less effect of the film thickness and deformation rate (<100 mm/min) on the EWF terms. On the other hand, the specific essential work of fracture (w(e)) at high load rate (1.2 m/s) approached the yielding-related term (w(e,y)) obtained at static loading rates (<100 mm/min).