Background The Early Warning Score (EWS) is a validated tool that has improved patient outcomes internationally. This scoring system is used within the hospital setting to identify potentially deteriorating patients, thus expediting referral to appropriate medical personnel. It is increasingly recognised that there are other influencing factors along with EWS, which impact on nurses’ decisions to escalate care. Aim The aim of this review was to identify and synthesise data from qualitative studies, which examined factors influencing nurses’ escalation of care in response to patients’ EWS. Methods The systematic search strategy and eligibility criteria were guided by the SPIDER (Sample Phenomenon of Interest Design Evaluation Type of Research) framework. Eleven databases and five grey literature databases were searched. Titles and abstracts were independently screened in line with pre‐established inclusion and exclusion criteria using the cloud‐based platform, Rayyan. The selected studies underwent quality appraisal using CASP (Critical Appraisal Skills Programme, 2017, https://www.casp-uk.net/casp-toolschecklists) and subsequently synthesised using Thomas and Harden's thematic analysis approach. GRADE–CERQual (Grading of Recommendations Assessment Development and Evaluation–Confidence in the Evidence from Reviews of Qualitative research) was used to assess confidence in results. The EQUATOR listed guideline ENTREQ (Tong et al., 2012, BMC Medical Research Methodology, 12) was used to synthesise and report findings. Results Eighteen studies from seven countries including 235 nurses were identified. Following synthesis, four analytical themes were generated with eighteen derived consequent findings. The four themes identified were as follows: 1) Marrying nurses’ clinical judgement with EWS 2) SMART communication 3) EWS Protocol: Blessing and a Curse 5) Hospital Domain. Conclusion Nurses strive to find balance by simultaneously navigating within the boundaries of both the EWS protocol and the hospital domain. They view the EWS as a valid essential component in the system but one that does not give a definitive answer and absolute direction. They value the protocols’ ability to identify deteriorating patients and convey the seriousness of a situation to their multidisciplinary colleagues but also find it somewhat restrictive and frustrating and wish to have credence given to their own intuition and clinical judgement.