Sugar-sweetened beverage (SSB) excise taxes are promoted as a key policy to reduce cardiometabolic diseases and other conditions, but comprehensive analyses of US SSB taxes have been difficult due to the absence of suitable methodologies to account for confounding factors. We use new quasi-experimental methods to estimate the overall effect of SSB taxes implemented in five large cities in the US: Boulder, Philadelphia, Oakland, Seattle, and San Francisco. We evaluated changes in SSB prices and volume purchased in these cities in the two years following tax implementation, compared to control groups constructed from other cities. We find prices of SSB products increased by an average of 33.1% (95% CI: 14.0%,52.2%; p<0.001) over the 2 years following tax implementation, corresponding to an average price increase of 1.3 cents per ounce and a price pass-through rate of 92% from distributors to consumers. SSB purchases in total volume declined by an average of 33.0% (95% CI: -2.2%,-63.8%; p=0.035) following tax implementation, corresponding to a price elasticity of demand of -1.00. Both effects were immediate and sustained, and we found no evidence of increased cross-border purchases following tax implementation. Scaling SSB taxes nationally could yield significant public health benefits.