Abstract: To ensure sufficient resources for the operating day, the system operators still execute out-of-market corrections (OMCs) after the day-ahead market. At present, the OMCs cope with the difference between the day-ahead market and the operational boundaries, which guarantees safe and reliable scheduling results. However, since the OMCs are not a market process, the non-market adjustments affect the efficiency of the electricity spot market. Therefore, the impact of OMCs on the spot market needs further analysis. This paper introduces the market frameworks and the OMC processes in typical countries, and provides the cause analysis of OMCs. Through the numerical results, the market impact of OMCs undergoes quantitative assessment from the aspects of market surplus and market operating cost. By studying typical market frameworks in foreign countries, this paper aims to provide a reference for modeling non-market allocation and improving market efficiency in China's electricity spot market.