Although AJCC8 provides improved prognosis stratification of cutaneous squamous cell carcinoma (CSCC) over AJCC7, T3 has a variable prognosis.To define prognostic subgroups in T3-AJCC8 CSCC.Retrospective cohort study of 196 primary T3-AJCC8-CSCCs. We conducted multidimensional scaling analysis using the six risk factors that define T3-CSCCs. The prognoses of the groups obtained were analyzed by means of competing risk analysis.Group-1 was characterized by a tumor thickness >6 mm (without invasion beyond the subcutaneous fat), alone or in combination with a tumor width of ≥4 cm. Group-2 was characterized by the presence of either invasion beyond the subcutaneous fat or by the involvement of nerves (≥0.1mm, or deeper than the dermis. Group-3 was characterized by the combination of both T3b risk factors, or of ≥3 risk factors. Group-3 (tentatively named T3c) patients had the worst prognosis for disease-specific poor outcome (DSPO) events and major events, Group-2 (T3b) had an intermediate risk, and Group-1 (T3a) had the best prognosis. (DSPO, HR=1.94, P=0.00009; major events, HR=2.55, P=0.00001; and disease-specific death HR=10.25, P=0.0009).Retrospective study.There is statistically significant evidence that T3-AJCC8 may be classified into distinct prognostic subgroups.