A numerical investigation was carried out to simulate the experimental results previously obtained concerning two-dimensional in-plane crack propagation in laminated glass fiber-reinforced polymer (GFRP) plates. The plates were designed with an embedded circular pre-crack and subjected to quasi-static out-of-plane loads. In order to study the transition from standard fracture mechanics tests, where the crack propagates only in one dimension (1D), to two-dimension (2D) scenarios, additional double cantilever beam (DCB) experiments were carried out on the same material system. Three-dimensional finite element models were developed for the simulation of the experimental fracture responses and cohesive elements were used to take into account the fracture mechanisms acting on the fracture process zone. A much higher value of for the total strain energy release rate (SERR) was numerically obtained for the 2D plates (compared to 1D double cantilever beam (DCB) specimens), which was correlated to an increase in the fiber-bridging area due to additional stiffness mechanisms activated in the plate.