Background and purpose Most centres cross-match between 2 and 4 units of blood pre-operatively for primary total hip arthroplasties (THA), but is this necessary? We aimed to quantify the use of blood after THA in our centre and to advocate a safe, evidence-based protocol for its use. Method A retrospective analysis of blood transfusion requirements of 169 consecutive total hip arthroplasties over a 12-month period. Results Out of the 460 units of blood that were cross-matched only 175 units (38%) were used. Only 22 of the 175 units (13%) were transfused on the day of surgery. No patients needed intra-operative transfusion or blood urgently. Inference We conclude that blood should not be routinely cross-matched for primary THA. We advocate a policy of only group and saving of blood in the majority of patients undergoing primary THA and cross matching blood if and when necessary. However, the 1-2% of patients who have antibodies present in the blood as per group and screen should have blood cross-matched and available pre-operatively. We believe this protocol, is safe and cost effective, resulting in a significant saving in cost, without compromising safety.