So, the 2025 premium without any subsidies would be $2,472 for someone earning $150k. The 2026 premium without any subsidies would be $2,906. Assuming it's exactly the same plan, same coverages, etc. (which it might not be, if they changed maximum oop and/or deductibles/copay levels) about a 17.5% premium increase.

Your cost with enhanced subsidies in 2025 but without enhanced subsidies in 2026 at 150k goes up from $1063 to $1245 or a little over 17% which seems to track the premium increase. It's not exactly comparable since we don't know what the 2025 cost would have been absent enhance subsidies.

However, a clue to how irrational ACA is, is that if the enhanced subsidies were retained for 2026, the net cost to you would actually go down from 1063 to 1058. It's not a lot, but what's the rationale for having the taxpayers absorb the entire premium increase, rather than a proportional share of it?

Not asking you to actually explain it.