Background Total en bloc spondylectomy (TES) is a widely accepted surgical technique for primary spinal bone tumours but is frequently accompanied by substantial peri-operative blood loss. Prior studies have reported estimated blood loss (EBL) can reach up to 3,200 mL. The aim of this study is to estimate the blood loss during TES procedures performed in the last ten years at our tertiary referral centre and compare EBL with actual blood loss (ABL). Methods We performed a retrospective review of all cases managed surgically with TES referred to our centre between 2005 and 2015. We recorded the oncological characteristics of each tumour and surgical management in terms of resection margins, operative duration and instrumentation. Data relating to peri-operative blood loss was also recorded including an estimation of total blood loss, the use of cell salvage where applicable and transfusion rates. Results A total of 21 patients were found to meet our inclusion criteria. There were 11 men and 10 women, with a median age of 40 years. The mean total ABL was 3,310 mL. Total operation time ranged from 6.53 to 19.7 h. Compared to ABL, in 59% of cases EBL had been underestimated by an average of 78% by volume. The EBL of the remaining 41% cases had been overestimated by 43%. This was not statistically significant (P=0.373). Cell salvage was used in 62% patients with a mean blood loss of 2,845 mL (884–4,939 mL) and transfusion of 3.8 units (0–12 units) versus 4,069 mL (297–8,335 mL) and 9.3 units (0–18 units) in those not managed with cell salvage. There was no significant difference in ABL between the cell salvage and non-cell salvage groups. Conclusions We report one of the largest case series in TES for primary bone tumours. EBL is not a reliable predictor for ABL. A large blood loss should be anticipated and use of cell salvage is recommended.