ABSTRACT Previous studies conclude that governments fulfill a large share of their campaign pledges. However, only a minority of voters believe that politicians try to keep their promises, and many voters struggle to recall the fulfillment or breaking of salient campaign pledges accurately. I argue that this disparity between the public perception and empirical evidence is influenced by the information voters receive throughout the electoral cycle. I expect that the media extensively inform readers about political promises. In addition, I posit that news outlets focus more on broken than on fulfilled promises and that the focus on broken promises has increased over time. I find strong support for these expectations based on a new text corpus of over 430,000 statements on political commitments published between 1979 and 2017 in 22 newspapers during 33 electoral cycles in Australia, Canada, Ireland, and the United Kingdom. Newspapers inform voters regularly about announced, broken, and fulfilled promises. Yet, across the four countries, newspapers report at least twice as much on broken than on fulfilled promises. Moreover, this negativity bias in reports on political promises has increased substantively. The results have implications for studying campaign promises, negative information in mass media, and the linkages between voters and parties.