Background: A subarachnoid hemorrhage due to an aneurysmal rupture (aSAH) is a serious condition with severe neurological consequences. The World Federation of Neurosurgical Societies (WFNS) classification is a reliable predictor of death and long-term disability in patients with aSAH. Poor-grade neurological conditions on admission in aSAH (PG-aSAH) are often linked to high mortality rates and unfavorable outcomes. However, more than one-third of patients with PG-aSAH may recover and have good functional outcomes if aggressive treatment is provided. We developed a risk model called Identifying POor GRade Outcomes (IPOGRO) to predict 6-month mRS outcomes in PG-aSAH patients as a secondary analysis of a previously published study. Methods: All consecutive patients in poor-grade neurological conditions (WFNS IV-V) admitted to our institute from 2010 to 2020 due to aSAH were considered. Clinical and neuroradiological parameters were employed in the univariable analysis to evaluate the relationship with a 6-month modified Rankin Scale (mRS). Then, a multivariable multinomial regression model was performed to predict 6-month outcomes. Results: 149 patients with PG-aSAH were included. Most patients were surgically treated, with only 33.6% being endovascularly treated. The 6-month mRS score was significantly associated with clinical parameters on admission, such as lowered Glasgow Coma Scale (GCS), leukocytosis, hyperglycemia, raised Systolic Blood Pressure (SBP), greater Simplified Acute Physiology Score (SAPS II score), increased initial serum Lactic Acid (LA) levels, and the need for Norepinephrine (NE) administration. Neuroradiological parameters on the initial CT scan showed a significant association with a worsening 6-month mRS. The IPOGRO risk model analysis showed an association between a WFNS V on admission and a poor outcome (mRS 4-5), while raised SBP was associated with mortality. Conclusions: Our IPOGRO risk model indicates that PG-aSAH patients with higher SBP at admission had an increased risk of death at 6-month follow-up, whereas patients with WFNS grade V at admission had an increased risk of poor outcome but not mortality.