Purpose: Acute appendicitis is a common surgical emergency worldwide, with significant variations in prevalence, presentation, and outcomes between high income countries (HIC) and low- and middle-income countries (LMIC). Complicated appendicitis has significant implications for LMICs because of limited healthcare resources and infrastructure. Although there is a plethora of evidence for HICs and appendicitis, the evidence for LMIC is lacking. This systematic review aimed to assess and compare the prevalence of complicated appendicitis among low-income countries and lower-middle income countries. Methodology: A systematic review of the literature was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PROSPERO CRD42024526007). Observational studies and randomised controlled trials (RCTs) published in PubMed, MEDLINE, Embase, and Scopus between 1990 and 2024 were retrieved. The primary outcome investigated was incidence of complicated appendicitis. Meta-analysis was performed using RStudio Software version 4.3.2. Results: Eighty-seven articles with 25,582 participants were included. Meta-analysis identified an increased pooled proportion of complicated appendicitis (34% [95% CI 27—41%] vs 23% [95% CI 19—27%] p<0.001), increased post-operative morbidity (19% [95% CI 13—27% p<0.01] vs 13% [95% CI 8—20% p<0.01]) and mortality (OR 2.36) in low income countries compared to lower-middle income countries. Conclusion: Appendicitis continues to be a morbid disease in low and lower-middle-income countries. This burden is particularly evident for low-income countries and has significant implications for management.