Combo testing for plans with different nra

We have a cash balance plan with NRA of 62+5 and a 401k plan with NRA of 65+5. For 401a4 testing what NRA do you use? Note that software seems to only allow one NRA assumption. I am inclined to use 62+5 since that would be the least advantageous for NHCEs in the k plan. But technically should you test under both NRAs? Or somehow test using different NRAs for each plan?

I thought you had to have the same NRA to combo test them. If I'm right about that, the 401(k) plan could be amended to 62/5 to match the cash balance plan.

Generally you would need to use the latest normal retirement age under the plan. See the definition of "testing age" in 1.401(a)(4)-12 for more info.

Since the DB plan has the earlier NRA, it's going to get messy. You still need to convert the hypothetical pay credit to a benefit accrual at age 62 using the plan's interest crediting rate and definition of actuarial equivalence, but then you will need to normalize that benefit accrual to age 65 using the testing assumptions before you can aggregate it with the EBAR from the DC plan.

It will make your life much easier if you can amend the plans to have the same definition of NRA. The DC plan will be easier to amend.

CBZ is absolutely correct and you should definitely have DCP amended to match NRA in CBP.