Background: This study predicts the implications of under-reporting of alcohol consumption in England for alcohol consumption above Government drinking thresholds. Methods: Two nationally representative samples of private households in England were used: General LiFestyle survey (GLF) and Health Survey for England (HSE) 2008. Participants were 9608 adults with self-reported alcohol consumption on heaviest drinking day in the last week (HSE) and 12 490 adults with self-reported average weekly alcohol consumption (GLF). Alcohol consumption in both surveys was revised to account for under-reporting in three hypothetical scenarios. The prevalence of drinking more than UK Government guidelines of 21/14 (men/women) alcohol units a week, and 4/3 units per day, and the prevalence of binge drinking (>8/6 units) were investigated using logistic regression. Results: Among drinkers, mean weekly alcohol intake increases to 20.8 units and mean alcohol intake on heaviest drinking day in the last week increases to 10.6 units. Over one-third of adults are drinking above weekly guidelines and over three-quarters drank above daily limits on their heaviest drinking day in the last week. The revision changes some of the significant predictors of drinking above thresholds. In the revised scenario, women have similar odds to men of binge drinking and higher odds of drinking more than daily limits, compared with lower odds in the original survey. Conclusion: Revising alcohol consumption assuming equal under-reporting across the population does not have an equal effect on the proportion of adults drinking above weekly or daily thresholds. It is crucial that further research explores the population distribution of under-reporting.