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Atmospheric methane levels were nearly steady between 1999 and 2006, but have been rising since then. Increases in wetland emissions, the largest natural global CH4 source, may be partly responsible. Tropical regions like Amazonia, host some of the largest wetlands on Earth, but there are few in-situ observations, which allow large-scale flux estimation. To improve estimates of its contribution to the global CH4 budget we measured 590 lower-troposphere methane concentrations vertical profiles at four Amazonian sites between 2010 and 2018. We estimate that Amazonia emits 46.2±10.3 TgCH4 y-1 (~8% of global emissions) with no emission trend. Non-fire sources (mainly wetlands) dominate emissions, with a smaller biomass burning contribution (~17%). We find a distinct east-west contrast with an emission peak in the northeast. Furthermore, while northwest-central Amazon emissions are nearly aseasonal, consistent with weak precipitation seasonality, southern emissions are strongly seasonal synchronously with equivalent water thickness seasonality.