This study examines inflation convergence across the provinces of Iran over the period from March 2012 to March 2025 using the Phillips and Sul (2007) club convergence approach and monthly Consumer Price Index data. To investigate changes in the pattern of inflation convergence, the sample period is divided into two subperiods: 2012–2017 and 2018–2025. The year 2018 is identified as a structural break due to the sharp exchange rate depreciation, the reimposition of international sanctions, and the intensification of inflationary instability. The results indicate that inflation convergence exists across provinces in both subperiods; however, its structure changes substantially over time. During the first period, provinces are distributed across several convergence clubs, whereas in the second period, most provinces converge within a single dominant club. Nevertheless, differences in the speed and intensity of inflation adjustment suggest that the transmission and absorption of macroeconomic shocks have not been uniform across regions. These findings indicate that although inflation convergence became stronger after 2018, regional heterogeneity continues to play an important role in shaping provincial inflation dynamics and should therefore be taken into account in inflation analysis and policy design.