(1) Background: Anxiety disorders are among the most common psychiatric conditions and have a rising prevalence. Patients with anxiety disorders can, however, be deterred from seeking treatment due to associated stigmas and medication side effects. Evidence indicates that promising digital health solutions to address those concerns reside in the growing field of extended reality (XR). The limited literature synthesis from the perspectives of patients and healthcare professionals (HCPs) regarding the experiences and effectiveness of XR-based anxiety disorder therapies motivated the undertaking of this systematic review. (2) Methods: A systematic search of the literature was conducted according to the PRISMA 2020 guidelines on the following databases: CINAHL, APA PsycNet and PubMed. The search was completed on 23 January 2024 with no restriction on the time of publication. Studies were screened based on a predetermined selection criteria relevant to the research aims. (3) Results: Five studies fulfilled the inclusion requirements. The majority investigated the use of XR tools for individual therapy and indicated that they can be as effective for patients as traditional methods and can aid in HCPs’ therapeutic tasks. (4) Conclusions: XR-based anxiety disorder therapies are generally perceived as immersive and with minimal side effects by patients, while HCPs mostly consider XR tools as practical and assistive. However, refinements with the XR setup could further improve the experience. Such modalities represent potent drug-free alternatives or supplements to traditional therapy and could be considered for remote, individual care. The findings’ generalisability requires further research into more conditions within the anxiety disorder group, as well as larger sample sizes.