If they have lived on $80k/year, the entire penalty per year is only $8k/year to withdraw that amount of their income from their 401k. This seems like a non-issue entirely unless they want to dramatically increase their spending.
Without knowing their goals/situation, it's pretty much impossible to know what the right actions here are.
Are they planning on retiring now completely? Do they have any taxable assets? How much of their 80k do they save vs spend currently? What are their actual goals?
72(t) seems like a pretty good thing for them to calculate here. But again, you have to have better context on their goals as to whether it makes sense. At age 40, life expectancy is 45.7 years, so that results in about 110k/year in 72(t) payments ($5M / 45.7).
My
guess is that using the 72(t) payment approach is probably what makes the most sense here.
Do they have a mortgage? If so, how much would it cost to pay it off?
The "don't pay off your mortage" folks might disagree, but this could be a case where it makes some sense. If they are paying a monthly mortgage, withdrawing money (and paying the taxes and penalties) from their 401k to pay it off will instantly increase their cash flow by that amount (they will still have taxes and insurance). If they are relatively mustachian, do they really need want or need to double their income every month at the expense of significant penalties and taxes? For most people, living on their current salary but not having to pay rent or mortgage would feel like a significant boost. Also, I presume they have already dialed their 401k contributions to the minimum necessary to get any match or benefits? They should also look hard at their other saving/investment habits. There's no sense paying penalties to withdraw money from the 401k if they are still squirreling away money every month.
In order to get the money to pay the mortgage off they will have to get it somewhere, which in this case seems to be from their 401k via an early withdrawal/penalty, which defeats the benefit here.
7) NUA if any part of the 401(k) is in company stock. Not really a withdrawal method per se but something to look into.
Also, if this is a concentrated 401(k), they should strongly consider diversifying to protect the $5M.
If I were in their shoes, I'd probably do the 10% penalty for the first five years or so while also starting a Roth conversion ladder. 20 years is too long to do a 72(t) IMHO, especially if there are kids in the picture because kids have a tendency to make budgets doubleplus-unsmooth.
It really depends. A Roth conversion ladder is going to eat up a ton of taxes if you are basically converting 2x your spending each year (assuming they have no already-taxed assets to live on for the first 5 years). They'd probably be better off just paying the 10% penalty every year, because the entire Roth conversion pipeline will be taxed at marginal rates. But this all depends on their yearly spending and what their goals are.
However, for someone earning 80k with a family, I'm guessing the Roth conversion pipeline will be worse financially.