I am an Irish EU passport holder but

Schengen visa info states the 90 in 180 days rule also applies to EU citizens.

Depends on when you spent 2 months in the EU and when you are coming back. If it were Jan/Feb and you come back on July 1st the 90 days starts again. If it were Apr/May and coming back this week then the time you spent earlier would count. eg you were here for April and May and coming back on June 20th then you would be allowed a further 29 days. 

Use the Schengen Calculator and input the date you are arriving and the dates you already spent here

https://ec.europa.eu/assets/home/visa-calculator/calculator.htm?lang=en#

AFAIK, As an EU passport holder the clock restarts as soon as the leave the Spain. So you could legally return to Spain the day after you arrive in the UK.

Edit...Looks like I'm wrong. I think things changed in 2012, just seen this quote "How Long can an Irish citizen stay in Spain?

Irish citizens can stay in Spain for up to 3 months without needing to obtain Spanish residency. If you plan to live in Spain for more than 3 months, you’ll need to get a Certificate of Registration after arriving in Spain. Alternatively, you can leave before the 3-month mark and and re-enter Spain after 180 days.

  "

https://housinganywhere.com/Spain/moving-to-spain-from-ireland-spanish-residency-for-irish-citizens

Also see https://upsticks.es/residency-in-spain-for-irish-passport-holders-all-you-need-to-know/

"Even if you’re not thinking of applying for residency in Spain, an Irish passport (or any EU passport) means you will not be subject to the 90/180 days Schengen area travel restrictions."

A classic example of theory v practice!

Yes strictly speaking even EU passport holders are subject to the Schengen 90 day rule whereas in reality they can come and go as they please without anybody bothering them or asking questions.

Many tens if not hundreds of thousands do just that, including Brits until the 'B' word queered their pitch.

Is it correct, no but Spain have long turned a blind eye to it.

Citizens who are EU nationals can travel within the area visa-free and with no restrictions on the amount of time they spend in each country. Non-EEA nationals can travel to Schengen without a visa, but they cannot stay for longer than 90 days in 180.

It is important to remember If at the end of the year (counting the calendar year, from January to December), you add up all the days you have been in Spain and they are more than 183, you are a resident for tax purposes. 

You may find these links useful:

https://www.citizensinformation.ie/en/travel-and-recreation/passports/irish-passports-an-overview/#:~:text=when%20this%20happens.-,Where%20can%20I%20travel%20on%20my%20Irish%20passport%3F,for%20up%20to%203%20months.

https://www.dfa.ie/irish-embassy/spain/our-services/new-to-spain/residency-and-entry-requirements/

I came back into Spain and at the airport they just looked at my passport and never recorded anything, not on a scanner or anything so technically how do they record I am here

When you fly you have to fill in advance passenger information (API). The airlines provide this information to border force at departure and arrival points. This can be/is used to track who flies in/out of a country.

  What is not tracked in the EU Schengen zone is cross border travel by road, so if you travel by car you re only recorded at the point you enter the Schengen zone. I don't know how a EU country checks how long a person travelling by road spends in each country, though remember, Google knows where you are!

Rgds,

Aitch. 

As an EU passport holder the Schengen 90/180 rule DOSN'T apply. You can make as many trips to any or all EU Schengen countries and it dosn't matter. The ONLY restrictions that apply are 1) that if you stay over 90days continuous, then you are required to sign on the Padron, which notifies the authorities and is used to allocate tax revenue to those areas. and 2) If you stay for more than 183 days in a tax year (Jan -Dec) then you become tax resident and have to pay tax in that country.

Each time you leave that country the 90 day clock resets and only starts when you enter the next EU Schengen  country. For example, if in spain and spent 88 days there and went to Gibraltar on a day trip and returned on day 90 then this becomes day 1 again but if you do this twice then you are very close to tax residency

1. You are not always considered tax resident in Spain after 183 days.

There is a proof that allows you to justify before the Tax Agency and avoid being considered as a resident for tax purposes, thus avoiding the payment of many taxes in the Spanish territory.

A proof issued by the country of origin or in which you have your main economic interest to justify that you are really resident there, and therefore you will not have to pay taxes as a resident in Spain.

In the case that a person can obtain the so-called tax residence certificate in his or her country, the Tax Agency will not consider that person as a tax resident, even if he or she is in Spain 183 days a year. This certificate works according to the regulations of the agreement between Spain and that country, generated through a double taxation agreement, so it does not have the same interpretation in all countries.

In addition, it is valid only and exclusively for one year. This means that it is valid for the year in which you apply for it, and you will have to apply for it year after year to continue participating in this exception, if you so wish and your situation applies.

https://centregestor.es/en/tax-residency-in-spain-how-to-know-if-you-are-a-resident-or-not/#:~:text=Staying%20more%20than%20183%20days%20a%20year%20in%20Spain&text=If%20at%20the%20end%20of,a%20resident%20for%20tax%20purposes

2. If you want to remain in an EU, EEA state or Switzerland for more than 90 days in any one visit you may be asked to show that you are:

• In employment
• Self-employed
• A full time student with health insurance and money to support yourself
• You have money to support yourself and health insurance (for you and your family) without state assistance
• You can Register on the Modelo EX18 at a Policia Nacional Office if you, as an EU citizen, want to remain more than 90 days in Spain in any one visit  but people normally do that if it is their intention to continue on to Residencia. Similatly with the Padrón. People register for Residency purposes. 
• You enter the Schengen Area at the first Schengen external border whether by air or by sea or land with your car or whatever mode of transport  you use.  After that there are no further borders between Schengen countries.
• Because some EU countries are not in the Schengen Area it doesn't mean they are lesser  EU  citizens or can be treated differently to those inside the Schengen area.

Bee