INTRODUCTION: Tailgut cysts, or retro-rectal cystic hamartomas, are rare congenital lesions arising from embryonic hindgut remnants, typically located in the retro-rectal area. These cysts present some diagnostic challenges due to vague symptoms and potential for malignancy. CASE PRESENTATION: A 25-year-old female presented with a 5-year history of perianal swelling. MRI revealed a T2 hyperintense, multiseptated cystic lesion suggestive of a tailgut cyst. The cyst was surgically excised via a trans-sacral approach, and the specimen was sent for histopathological analysis. CLINICAL DISCUSSION: The MRI findings were confirmed by histopathology, identifying a benign tailgut cyst. The patient had an uneventful recovery and was symptom-free at the 2-month follow-up. CONCLUSION: Tailgut cysts can mimic other perianal masses, complicating diagnosis. Accurate diagnosis and successful treatment rely on clinical vigilance, advanced imaging, and histopathological confirmation. Early surgical resection is crucial to prevent complications, including malignancy.