Tobacco and alcohol are frequently used together, and this may be partly explained by a distinct profile of subjective effects associated with co-administration. Ecological momentary assessment studies have examined effects of naturally occurring co-use, but, to date, have not assessed differing effects as alcohol levels rise and fall.The objective of the study was to describe subjective states and appraisals of cigarette and alcohol effects reported during the entirety of real-world drinking episodes.Currently-smoking frequent drinkers (N = 255) carried electronic diaries for 21 days. Analyses focused on reports made during 2,046 drinking episodes. Signaled prompts intensively oversampled moments in the hours following consumption of the first drink in an episode. Multilevel regression analyses were used to predict ratings of buzz, dizziness, excitement, and sluggishness as a function of person-level and contextual covariates, estimated blood alcohol concentration (eBAC) level, ascending vs. descending eBAC, smoking, and their interactions. Appraisals of cigarette and alcohol effects were also examined within this framework.Buzz, excitement, and pleasure from alcohol and cigarettes were prominent features of real-world drinking episodes. Smoking was associated with enhanced buzz and excitement when eBAC was high and descending. Smoking slightly accentuated the relation between eBAC and ratings of drinking pleasure among women, but this relation was somewhat weakened by smoking among men.Smoking during drinking episodes may be partly explained by a persistence of stimulant alcohol effects beyond the blood alcohol concentration peak. Acute effects of nicotine and tobacco use on the descending limb deserve further scrutiny in experimental alcohol challenge research.