With standard treatment for glioblastoma (GBM) consisting of surgery followed by radiotherapy (RT) with concurrent and adjuvant temozolomide (TMZ), median survival is ~14.6 months. This is not as informative to patients who have survived for some time. Conditional probability of survival may offer more relevant survival estimates. Outcomes/conditional probability of survival and post-progression survival (PPS) estimates were retrospectively reviewed in the TMZ treatment era of 882 consecutive patients with a diagnosis of GBM from January 2004 to August 2010. Median age of entire cohort was 62 years including 62 % males. Baseline performance status (PS) was 0-1 in 67, 23 % had frontal lobe tumors, 58 % received concurrent RT/TMZ ± adjuvant TMZ. Survival (OS) was similar for those with frontal lobe tumors versus other locations (P = 0.25). OS for patients receiving standard RT/TMZ ± TMZ was 14.2 months. Age, PS, extent of surgery, therapy post-surgery had significant effects on OS. OS for entire cohort at 1, 2, 3, 4, 5 years was 43.4, 17.9, 10.4, 8.4, 7.2 % respectively. Conditional probability of survival of an additional year given survival to 1, 2, 3, 4, 5 years was 41.4, 58, 80.7, 85.7, 81.5 % respectively. Conditional probability of survival for those patients receiving concurrent RT/TMZ ± adjuvant TMZ was similar. Patients who progress >18 months after their initial treatment for GBM had significantly greater 2 and 5 year PPS as well as OS. Conditional probabilities of survival may provide more meaningful life expectancy predictions for survivors of GBM than conventional survival outcomes.