This paper investigates the performance of reconfigurable intelligent surface (RIS)-assisted LoRa networks. Specifically, we consider a LoRa system enhanced by RIS under the influence of hardware impairments and asymmetric channel conditions. A closed-form expression for the outage probability at end devices is derived using the method of moments. The accuracy of the proposed analytical framework is extensively validated through Monte Carlo simulations. Several important insights are drawn from both the theoretical analysis and simulation results. In particular, the system’s performance is significantly enhanced by an increase in the number of RIS elements and the transmission power of the gateway. Furthermore, comparisons with related works described in the literature are made to show that the proposed system outperforms these existing approaches simply by increasing the number of RIS elements. Additionally, we reveal that a higher spreading factor (SF) does not necessarily lead to worse performance than a lower SF, and the impact of hardware impairments is found to be minor under typical operating conditions.