AbstractUnderstanding nonstationary tides in tidal rivers is a major contemporary challenge. In particular, the response of river tides to natural developments in the estuary remains poorly investigated. This study analyzes the evolution of tidal characteristics over the last six decades in the Garonne Tidal River (GTR, SW France), in order to explore the effect of natural and human‐induced morphological and hydrological changes on river tides. The tidal Garonne is an excellent example, as it has been subject to decreasing river discharges, natural morphological changes, and gravel extraction. Tidal range (TR), distortion (AM4/AM2), and asymmetry direction (2ϕM2‐ϕM4) were calculated at four locations from the water level time series of 1953, 1971, 1982, 1994, 2005, and 2014. The annual time series of M2 and M4 amplitudes and phases were obtained through complex demodulation. Results reveal that both TR and 2ϕM2‐ϕM4 have increased since the 1950s. River flow modulates TR and AM4/AM2 significantly. A long‐term decrease in summer discharges from 200 ± 50 to 100 ± 50 m3 s−1 would increase TR by +11.5% in the upper GTR. Natural morphological changes amplified TR and 2ϕM2‐ϕM4 by up to +12–15% between 1953 and 2014. TR and 2ϕM2‐ϕM4 doubled in the regions affected by gravel extraction between 1953 and 1971. Further, the persistence of mobile mud in the GTR increased TR seasonally but also interannually (by up to +16% in winter and spring of dry years). The potential impact of these changes on suspended sediments is discussed, revealing complex feedback between the evolution of hydrology, morphology, tides, and sediment trapping.