We investigate the kinetic features of complex charge transfer chemical reactions using a microelectrode integrated in a flow cell made with 3D printing technology. Thin layer electrochemical cells with 350 μm (height) × 1000 μm (width) channels were designed. Ferrocyanide oxidation on a 100 μm diameter Pt electrode using the printed cell showed mass transfer limiting current at large overpotentials. The variation of the limiting current with the flow rate (1 μL/min ≤ Q ≤ 100 μL/min) was interpreted with the superposition of a constant current due to radial diffusion and a Levich-type square-root relationship, indicating a mixed radial diffusion/thin layer mass transport condition. These findings were further supported by numerical simulation of a diffusion-convection equation in the flow channel. Experiments with copper electrodissolution in phosphoric acid electrolyte reproduced oscillatory behavior that was previously seen in macrocells and polydimethylsiloxane (PDMS) microchips. The 3D printed cell can accommodate multiple electrodes – to demonstrate this application we showed that the current oscillations with copper electrodissolution can exhibit frequency synhcronization with a dual electrode configuration. Finally, hydrogen oxidation on a Pt wire in the presence of Cu2+ and Cl− inhibitors displayed bistability at relatively large external resistance and oscillations at high volumetric flow rates. The results show that the 3D printed thin layer design is an alternative to studying nonlinear phenomena in electrochemical cells with distinct advantages to the traditional approaches of using macrocells and PDMS microchip flow cells.