Schengen Again: UK/Ireland & Portugal Rotation

If I wanted to permanently relocate to Europe, I would choose one country and apply for permanent residency. A tourist visa is not really for those who want to live in Europe permanently. You also lose out on the benefits of citizenship (right to work, ability to sign up for their excellent healthcare, etc) as a tourist and you would need to make a living (hard to get permission for as a tourist, impossible for most) yet have a consistent income, pay for health insurance through short term insurance bought outside the EU, and miss out on so much EU or UK permanent residency/citizenship offers.

I'm in Lisbon now so returning to the US is not practical for me with no living family or friends to stay with for the three months it would take to obtain a 4 month residency visa, which is also extremely expensive and would lead to citizenship, perhaps, after five years. Due to austerity measures and other economic issues, there are no jobs and private health insurance is required for extension of a tourist visa. So these days, I see few benefits from pursuing permanent Portuguese citizenship.

My main concern is to not violate the terms of the Schengen Agreement. I was planning to buy a small apt with cash funds, but the volatility of the euro and the peculiar property market here make renting seem more viable.

You are not supposed to live in the UK on a series of 6-month visitor admissions. Every time you enter the UK you are assessed on a number of criteria which include:

"The requirements to be met by a person seeking leave to enter the United Kingdom as a general visitor are that he:
...
intends to leave the United Kingdom at the end of the period of the visit as stated by him; and does not intend to live for extended periods in the United Kingdom through frequent or successive visits;"

You may get away with it for a low number of successive visits, but as soon as your pattern is determined you would be refused entry.

Leaving for Ireland incidentally in the middle of a stay in the UK wouldn't stop the clock in the UK because of the common travel area. Laws in Ireland in the last decade as well as the UK have been tightened up regarding people staying for long periods without applying for proper residency.

Thanks, Marco, you are no doubt correct about a recurring pattern, though that language is vague. I should probably explain that I am elderly so "permanent" might only be a few years anyway. I intend to carry with me documentation of health insurance and proof of funds which might allay concerns that I would be taking advantage of the UK's social welfare programs.

Susan, you see "few benefits in pursuing Portuguese citizenship".
There is one big benefit. A Portuguese citizen, just like a citizen of any other EU country, has no time limit on their stay in any EU country. If you are within a few months of getting that citizenship it would be a great advantage,
I know of US citizens who have got Italian or Irish citizenship through their grandparents not in order to live in those countries, but to give them the right to live in another EU countries they do want to live in.
This is slightly ironic, as their grandparents wanted US citizenship, but the grandchildren are trying to reclaim their grandparents citizenship.

Marco is correct, the UK 6 month limit applies collectively to UK and Ireland (but not to EU citizens).
Yes, the UK does not have a fixed return limit (unlike the Schengen "90 days in 180" limit), but it does refuse entry if you come back too soon. There are no hard time limits.
And never mention work to immigration, a tourist is not allowed to work (but an EU citizen is)

There used to be a visa for retired people of independent means (income >£25k pa after tax) to come and reside in the UK but that was abolished in 2008. Even that required demonstration though of a prior close connection with the UK.

The UK rule on revisiting is 6 months in a 12 month period, but this is a separate criterion to the one I quoted above. A lot would come down to the opinion and discretion of the officer within the rules on entry, which cannot be relied upon.

I will have spent 6 months in Lisbon, with a ticket to London, where
I will stay six months. So as to avoid overstaying in the S zone

If you will have spent 6 months in Lisbon and you want to avoid overstaying Schengen visa limits you will have over stayed by 3 months. The normal visa waiver program limits are 90 days in any 180, not 180 days....

I am complying with Portuguese immigration requirements for extension of the tourist visa, as previously stated, so I won't have overstayed the 90 day tourist visa.

There are a lot of replies here, so my two cents worth is this:

The stay in the Schengen areas is 90 DAYS!! for an American citizen with no visa. Then you can go to England or Ireland and stay for another 90 DAYS, you have to be OUT OF THE SCHENGEN for a total of 180 days before you can re-enter. It does make it very difficult for US citizens to stay longer, but that is the way it is. Your 6 month stay is not correct.

Best thing to do is go to the US Dept of State website and read all about visas, get the information from the authorities. I could be wrong. I have looked into it as I would like to spend a year in Spain.

Your other option is to just not leave if that is your goal. Become an illegal just like millions in the US.

Each country in the Schengen area has its own regulations. I am not familiar with Portugal allowing you to extend your tourist visa for 3 months?? are you sure about that?

Sally, there is no requirement to be out of the Shengen Zone for 180 days before returning. If you have used your 90 days, you only have to be out for 90 days before you return.

Susan, by now you have met with Portuguese immigration. What happened?