People compare IULs by cap rate. The cap is the last thing that happens to your money. Four charges come first, and two policies with identical caps can land thousands apart because of them.
The premium load comes off every dollar as it arrives, before anything is credited to the account value. It covers state premium tax, the federal DAC tax, and part of the carrier's acquisition cost. Somewhere between 4% and 8% is typical, and some designs drop it after the first several years. On a $20,000 annual premium at 6%, that's $1,200 that never reaches the index.
The per-policy fee is a flat monthly charge, often $7 to $12. It's the same whether the policy is $100,000 or $5 million, which makes it a rounding error on a large policy and a real drag on a small one.
The per-unit charge is the one nobody sees coming. It's assessed per $1,000 of death benefit, monthly, and it's usually front-loaded into the first ten years and then goes away. This charge is why a policy stuffed with more death benefit than the client needs performs poorly. You're paying it on every thousand dollars of coverage you bought. Getting the death benefit down to the minimum the tax code allows for the premium being paid is most of what design work actually is.
Then the cost of insurance, charged monthly on the net amount at risk, which is the death benefit minus the account value. It rises with your age every year, and it shrinks as the account value grows and closes the gap. Those two forces fight each other, and which one wins depends on how fast the cash value gets built early.
What's left after all four goes into the index account and earns whatever the cap, participation rate, and crediting method produce. So the sequence runs charges first, credit second. An illustration showing 6.5% credited is showing you the number applied to what's left, not to your premium.
All of these are disclosed. They're in the contract and in the expense pages behind the ledger, and almost nobody reads that far, because the summary is up front and the charge detail is on page 14. Ask for the expense page specifically. If an agent can't produce it or can't walk you through it, that tells you something.
Current charges can also be raised to the guaranteed maximum stated in the contract. Carriers rarely do it, and rarely is not never. Look at what the guaranteed column shows next to the current one before you decide the policy works.