Abundant media outlets allow for much diversity of political messages and selective use among citizens. A 2-session online field study examined impacts of attitude consistency, attitude importance, and source credibility on selective exposure to political messages and subsequent attitude accessibility. The first session assessed attitudes and their accessibility. In the second session, participants browsed online search results that featured attitude-consistent and attitude-discrepant messages associated with sources of either high or low credibility; selective reading was tracked. Then attitude accessibility was measured again. Participants spent less time with attitude-discrepant messages compared to attitude-consistent messages; this pattern was particularly pronounced among participants with higher attitude importance. Low importance fostered exposure to high-credibility messages. Exposure to attitude-discrepant, high-credibility messages reduced attitude accessibility.