Background - Studies suggest text messaging is beneficial to health care; however, no one has synthesized the overall evidence on texting interventions. In response to this need, we conducted a systematic review of the impacts of text messaging in health care. Methods - PubMed database searches and subsequent reference list reviews sought English-language, peer-reviewed studies involving text messaging in health care. Commentaries, conference proceedings, and feasibilities studies were excluded. Data was extracted using an article coding sheet and input into a database for analysis. Results - Of the 61 papers reviewed, 50 articles (82%) found text messaging had a positive effect on the primary outcome. Average sample sizes in articles reporting positive findings (n=813) were significantly larger than those that did not find a positive impact (n=178) on outcomes (p=0.032). Articles were categorized into focal groups as follows: 27 articles (44.3%) investigated the impact of texting on disease management, 24 articles (39.3%) focused texting's impact to public health related outcomes, and 10 articles (16.4%) examined texting and its influence on administrative processes. Articles in focal groups differed by the purpose of the study, direction of the communication, and where they were published, but not in likelihood of reporting a positive impact from texting. Conclusions - Current evidence indicates that text messaging health care interventions are largely beneficial clinically, in public health related uses, and in terms of administrative processes. However, despite the promise of these findings, literature gaps exist, especially in primary care settings, across geographic regions and with vulnerable populations.