Final answer:
In a UL policy with level death benefit plus account value, what is not guaranteed is the accumulation of cash value over time, which can affect premium payments or policy validity.
Step-by-step explanation:
What is not guaranteed in a Universal Life (UL) policy with a level death benefit plus account value with the level cost of insurance is the accumulation of cash value over time. These policies combine a death benefit with a savings account component, where part of the premium goes towards the death benefit and another part is invested to build up cash value.
The cost of insurance (COI) in these policies remains level, which means it does not increase as the policyholder ages. However, if the investments do not perform well, or the cost of administering the policy is higher than anticipated, the cash value may not accumulate as expected. This could potentially result in the need for higher premium payments to maintain the same level of death benefit, or the policy could expire if the cash value is not sufficient to cover the insurance costs.