Well, it wouldn’t require lying but certainly it seems tricky. You can deregister before you leave the country and neglect to provide an address for where you are going – because you wouldn’t necessarily know in advance and you cannot provide information that does not exist. So they clear your address from your id card which then just has an empty address.

Correct me if I’m wrong, but you don’t have a specific legal obligation to state where you live abroad.

Though one snag is that you have a legal obligation to vote in elections and you must vote in the nearest embassy, which requires giving an address to get on the voting roster. However, voting is not strictly enforced. If you fail to vote there is a small fine but I don’t think they actually hit unregistered people abroad with that. If you do not vote in 3 consecutive elections, then you could lose your voting rights for a few years, I think.

I do not believe the bank gets a notification that you have deregistered. But at some point your ID card on the bank’s files will expire and they will expect an updated copy and freeze your account until they receive it.

If you walk into an embassy to “renew” your passport, do they demand an address? I would think you would pick up your passport at the embassy a week later. Or do they mail it?

Anyway, I can understand giving in to surveillance and disclosing US ties, but OTOH it seems like a nightmare to do what’s expected as well… to be tagged as a toxic US person. It’s a mess either way. Perhaps the wisest move is to “move” to Canada, stay there a couple months, setup residency, then move to the US and just neglect to mention it. Get mail forwarding from Canada.

Half their internet banking site is off-limits to me

Mind elaborating? Did they restrict your account specifically, or does the website simply treat logins from the US differently? I’m surprised you wouldn’t retain full cloud access so long as your account exists under the terms you signed up for.

I don’t understand why you would tell your Belgian bank that you left Belgium, particularly when your new residence is the US which flags you as a toxic asset that requires special handling. That could only work against you. Surely you would be better off not telling them you moved and use a VPN to Belgium to access your acct.