AFAIK at the moment, I will be in France when I get sold up here , under the EU rules,due to Irish citizenship, but due to US citizenship , will have to pay Uncle Sam. I will be retired, so I "should " file zero tax return in France (other than property taxes to pay) . all of my passive income will be US taxed by Uncle Sam. If anything changes in the future and I should pay tax in France, then under the double taxation treaty this is a USA deduction .

I think you're right about the net result, but probably not the process.

I believe you will be deemed to be a US national tax resident in France. France will tax you on your worldwide income, and you have to file there. You will also have to file in the US. The tax treaty means that you won't pay the tax twice...what you pay in one place will be a credit in the other place. But it does in general mean that you will pay the higher of the two countries' tax rates on each subcategory of income (salary, capital gains, dividends, etc), since they are generally non-refundable tax credits. And you have to file two tax returns. The exception is that I believe a certain amount of income for US citizens who are not US resident is exempted from US tax...for that portion, you will pay only the "local" rate, French in this case, rather than the higher of the two rates on that category of income.

As for using a French broker, I suspect (??) that you will find that as a French resident you will by law be required to use one registered to offer services in France. Many/most countries prohibit their residents from using brokerages which are not registered in that jurisdiction. Fortunately there are good choices now, like IB.

And again, as an EU resident, you will likely be prohibited from investing in things which are not allowed for EU residents, most notably US mutual funds and ETFs. I don't know if you would be allowed to continue holding ones you owned the day of your deemed arrival in Europe. EU mutual funds (UCITS) are horrible, as a rule. Very fragmented market, so fees remain high.

I know a lot of people in this general situation, and it's not so bad, other than the hassle of filing the 1040. The only hard thing is getting a regular bank account to pay your bills. Most banks absolutely will not touch US citizens, regardless of whether or not they are legal local residents, even if their spouse is an EU citizen.

Jim

PS, I strongly recommend you ask Manlobbi to pull your post with your email address in it.
You don't want that out there on the web.
Just invite people to reply using the "Email hummingbird" option at the bottom of the form.