How to find out if your deceased spouse had secret bank accounts and other assets?

It seems like they would leave a trail or tip somewhere to the booty.
try a PI

If they were “secret” then you have no way of finding them. They would be required to be in his name to be found – and if in his name, there would be an audit trail. (Unless he was also a tax cheat.) If a bank account or real property he would have to have a means of accessing them, bank cards, deeds etc. If you cannot find such things then you are likely to be wasting your time.

After a certain period of time (different amounts of time in different states), unclaimed funds go through what is called an escheatment process whereby the monies are turned over to the state. You can usually look this up on unclaimed funds websites available for most states. You would look it up by his name and fill out the forms with a copy of the certified death certificate and whatever documents that show you are the rightful heir.

I would also expect that you would receive mail (or he may get email) referencing any accounts. You might also get a bill one of these days for a post office box. If you are the rightful heir, you should be able to access any po box he may have maintained on the sly and learn if he has had bank statements sent there.