Ironman Switzerland Thun 2025: Age Group Stats and Qualification Times

As we’re in the busiest period of the Ironman calendar there were two races last weekend, the second being Ironman Switzerland Thun. Switzerland is a slightly slower European course, not one to choose specifically for a fast time. It comes with 40 slots for Kona in 2026, allocated via adjusted performances.

Result Distributions

Overall this year’s race isn’t too different from the results for the previous few years in Thun. The major difference appears to be the swim, although I think there’s a shorter swim in one of the previous results to pull down the swim times in the older data. Bike and run are very similar, perhaps slightly faster at the median, but not significantly.

DNF Rates

DNF rates are low for the course. The majority of years have been over 10%, but here we’re just under 8%. That seems to be a good level of DNF for this race.

Median Splits

Median splits are in line with the distributions. Meaning there’s no major patterns present in the comparison, times remain quite similar.

Competitor Origins

As with many of the European races there’s a wide mix of athletes competing; the majority of the field coming from outside of Switzerland. Slots are similarly widely dispersed under the new performance based system.

Performance Changes

Ironman Switzerland has a relatively short history in Thun. Looking over the data it’s quite consistent in timings with 2023 being the year that stands out (as it does in the DNFs).

Qualification

I’ve adjusted and ranked results and from that calculated the number of slots that would end up in each age group if no roll down takes place. Under the new system roll downs will directly affect the slots claimed by age groups. You can explore these numbers in more detail on the Ironman Switzerland qualification page.

Age Group Top 20

The majority of age groups have top twenty finishers close to the averages. A few stand out with some faster than usual times for the course. This tends to coincide with the age groups getting more sets due to higher performances.

Conclusion

Another race whose results are typical for the course. Not major differences from previous years and a low DNF rate for the race. The front of pack in this one also trend closer to the averages with only a few standing out.