Background: Non-traumatic subarachnoid haemorrhage (SAH) is a potentially life-threatening neurological emergency; most commonly associated with ruptured intracranial aneurysms. Computed tomography angiography (CTA) is widely used for vascular evaluation, whereas digital subtraction angiography (DSA) remains an important reference investigation for detecting and characterising intracranial vascular abnormalities. Aim: To compare CTA and DSA findings in patients presenting with non-traumatic SAH. Methods: This prospective, hospital-based, cross-sectional analytical study included 51 adult patients with non-traumatic SAH confirmed on non-contrast computed tomography. All patients underwent both CTA and DSA. Demographic characteristics, clinical presentation, haemorrhage distribution, vascular abnormalities, aneurysm morphology and measurements were evaluated. DSA was considered the reference standard for comparison. Results: The mean age was 52.0 ± 11.4 years, with female predominance (62.7%). Thunderclap headache was reported in all patients (100%), followed by vomiting (92.2%) and neck stiffness (64.7%). Aneurysmal SAH was identified in 32 patients (62.7%), while 19 (37.3%) had non-aneurysmal SAH. CTA demonstrated 39 aneurysms, whereas DSA demonstrated 40 aneurysms. The anterior communicating artery was the most frequently reported aneurysm location in both investigations. Most aneurysms were saccular and measured 5–10 mm. DSA additionally demonstrated other vascular abnormalities, including arteriovenous malformations, dural arteriovenous fistulae, Moyamoya disease and vasculitis. A documented small basilar tip aneurysm missed on CTA highlighted the potential limitation of CTA in detecting small lesions. Two patients experienced minor DSA-related complications. Conclusion: CTA demonstrated high reported diagnostic performance and excellent morphometric reliability. Nevertheless, DSA remains important for detecting very small aneurysms and subtle non-aneurysmal vasc