Accelerated corrosion testing has been an integral part of estimating the durability of protective coatings on metal substrates. Test methods such as salt spray and artificial ageing has been used extensively according to the requirements put forward by the ISO 12944 standards. The testing time depends on the corrosivity of the environment as well as the durability expected from the coatings. For the highest corrosion class, this can range up to 4200 hours (approx. 6 months). With the ongoing demand for coatings with higher durability (> 25 years), the testing time will be further increased. This in turn results in prolonged periods of testing requiring a huge number of resources. We therefore conducted a study to determine the presence of any trends in the corrosion creep observed in salt spray testing as well as artificial ageing. An epoxy with a polyurethane topcoat was chosen as the paint system, and salt spray tests according to ISO 9227 and artificial ageing according to ISO 12944-6 and 9 were conducted for various durations. Following the end of testing, the evaluation of degradation was performed using corrosion creep as a parameter. Visual examination was performed to observe any visible degradation. The barrier properties of the coating system were evaluated using Electrochemical Impedance Spectroscopy (EIS) according to ISO 16773-2. Supplementary data obtained from water condensation tests and adhesion pull-off tests shall as be presented as well. The identification of trends in such corrosion tests opens the possibilities of estimation of corrosion behaviour of paint systems based on a finite set of data.