The ulnar nerve block is a regional anaesthesia technique used for surgical procedures on the forearm and hand. The ulnar nerve originates from the medial cord of the brachial plexus (C8-T1) and travels down the medial arm before passing through the cubital tunnel at the elbow. It then enters the forearm, running deep to the flexor carpi ulnaris and alongside the ulnar artery. At the wrist, it passes through Guyon’s canal to innervate the medial hand. The nerve provides sensory innervation to the medial hand and fingers and motor control to the intrinsic hand muscles, including the hypothenar muscles, interossei, and medial lumbricals. This block is commonly performed for hand surgeries when upper arm tourniquet analgesia is not required. It is often combined with median and radial nerve blocks for hand anaesthesia. Ultrasound guidance improves precision by allowing direct visualisation of the nerve at the elbow or wrist, facilitating safe and effective local anaesthetic deposition. Compared to proximal brachial plexus blocks, the ulnar nerve block preserves proximal limb function, making it ideal for selective analgesia. It is a safe and effective technique with minimal complications when performed correctly.