In September 2026, the canton of Basel-Stadt recorded 117 total deaths, with 47 deaths among men and 70 among women. The overall mortality rate was 55.6 deaths per 100,000 inhabitants. Among men, 7 deaths occurred under age 65 and 40 at age 65 or older, yielding mortality rates of 8.2 and 46.9 per 100,000 respectively. Among women, 5 deaths occurred under age 65 and 65 at age 65 or older, with rates of 4.0 and 51.9 per 100,000. The most impacted group in absolute terms was women aged 65 and older, who accounted for 65 of the 117 deaths and had the highest age-specific mortality rate at 51.9 per 100,000.

Historically, for the month of September since 2005, the average total deaths were 159.7, with an average mortality rate of 81.5 per 100,000. The average deaths among men were 72.8 and among women 86.9. The average mortality rate for men was 77.3 per 100,000 and for women 85.3 per 100,000. In the previous year, September 2025, there were 126 total deaths, 63 men and 63 women, with an overall mortality rate of 60.7 per 100,000.

Compared with the historical average, September 2026 shows a substantial decline. Total deaths were 117, which is 42.7 fewer than the average of 159.7, and the overall mortality rate of 55.6 per 100,000 was the lowest recorded for September since 2005. Male deaths were also the lowest on record at 47, compared with an average of 72.8, and the male mortality rate of 45.8 per 100,000 was the minimum observed. Female deaths at 70 were below the average of 86.9, though not the lowest on record; the female mortality rate of 64.9 per 100,000 was also below average. The most striking relative decline was among men aged 65 and older, whose mortality rate of 230.7 per 100,000 was the lowest ever recorded for September, far below the average of 384.7 and the previous minimum of 259.9 in 2020. Women aged 65 and older also showed a lower rate of 282.6 per 100,000 compared with the average of 344.3, though this was not a record low. Deaths under age 65 were also low for both sexes, with male under-65 mortality at 8.2 per 100,000 versus an average of 16.1, and female under-65 mortality at 4.0 per 100,000 versus an average of 8.9. Overall, September 2026 stands out as an unusually low-mortality month, driven primarily by historically low death counts and rates among older men, with women also below average but less dramatically so.