(Romantic) Compatibility of Instinctual Matches

Most individuals who study the Enneagram eventually ask themselves:

“What kind of instinctual stacking would be the best match for me in a romantic relationship?”

Of course individual preferences vary, but there are two main factors that determine how helpful and satisfying an instinctual match is for you in a romantic (long-term) relationship:

Your first instinct being “soothed” by your partner (through their second, most balanced instinct) and/or you both being on the same wavelength – in the same “flow“.

Sexual Instinct *First* Compatibility

SX first individuals typically yearn for finding that “special someone”, so their priority should be finding someone who is “good” for them. Is that a fellow SX first person?

Sexual instinct (SX) first people typically fare the best with someone who is actually not a fellow SX first individual, on average. This may seem counterintuitive – because SX first people desire close intimacy so much, shouldn’t they be with another SX first person? But the opposite can be true.

We often desire what is not the best for us. With SX first people, they too late (or not at all) realize that a fellow SX first person often brings a very similarly neurotic attitude towards SX into the relationship (at average to unhealthy mental levels), which is rather counterproductive to the couple’s welfare.*

At the worst, the shared obsession with SX intimacy can lead to isolation, addictions and more. Additionally, SX first people have a tendency to “give their all” in romantic relationships and laser-focus on them, so it is best when their partner brings a much more balanced attitude towards SX into the relationship, so that neither one of them gets “burned out” or neglects other parts of life.

A person who is SX blindspot won’t be able to provide them with enough balanced intimacy, as well as not value it enough. 

In contrast, SX secondary people have the most balanced view on intimacy and SX matters (at average to healthy mental levels).

Best Matches

Following the above…

For Sx/Sp

  1. So/Sx
  2. Sp/Sx

*Possible exception/add-on: Two healthy Sx/Sp individuals.

For Sx/So

  1. Sp/Sx
  2. So/Sx

*Possible exception/add-on: Two healthy Sx/So individuals.

Problem with Blindspot Stacking (e.g Sx/Sp + So/Sx)

The only aspect that makes the same flow matches not the clear “winner” is the fact that one person’s first instinct is the other’s blindspot. In this case, that can lead to the SX partner being uninterested by the main concerns of their partner and their partner not getting their primary interest met.

For example, while the Sx/Sp individual benefits a lot from the balanced view on Sx from the So/Sx person, the latter does not get their So instinct-related neuroses soothed or interests met.

However, the upside to this match is the fact that both people are in the same flow and hence have the same attitude and priorities towards life. Also, their instincts cover all 3 instinctual aspects of life, making this couple well-rounded in their priorities.

It could be concluded that the ideal scenario for this match would include a healthy So/Sx individual – because in that instance, their amount of neuroses would be rather small and less significant.

However, a couple like this will go through tough times when the So/Sx person becomes unhealthy – their So-related neuroses emerging, they will seek out help in that area, which the Sx/Sp person is unable and unwilling to give.

For this couple, it can be crucial that the So/Sx individual is quite mentally healthy and balanced, though of course a healthy Sx/Sp individual will aid the couple’s welfare too.

Problem with same Blindspot-Stacking (e.g Sx/Sp + Sp/Sx)

In that respect, the exchange between Sx/Sp and Sp/Sx would be more stable during mental health fluctuations and instinctually equal, both individuals benefitting from the other’s second instinct – but at the cost of moving “against” the other’s life direction in some way or another, being in opposite flows.

Also, one instinct (their shared blindspot) would continuously get neglected in the relationship, which might be negative, especially if children are involved. Being blind to one area of life might be problematic.

That is why the opposite flow match is around the same level as the same flow match.

Sexual Instinct *Last* Compatibility

SX last individuals usually feel like they have a myriad of other things to do rather than to focus their attention on finding (and keeping) a romantic relationship.

SX last people may grow the most in a relationship with someone who is not a fellow SX last person. 

However, SX being their blindspot and therefore low on their list of relationship requirements, they will naturally gravitate towards to and feel the most comfortable with someone who shares all of their values and won’t try to “push” them for any special kind of intimacy.

In return, it’s going to be best if their partner doesn’t value Sx too highly either.

Best Matches

Following the above…

For Sp/So

  1. Sp/So
  2. So/Sp

For So/Sp

  1. So/Sp
  2. Sp/So

Those two matches are on the same level, because in the Identical stacking case, the couple will face identical blindspots and weaknesses, which can be a source of frustrations.

And in the other match, both people will be able to help the other with their first instinct, but they go in opposite flows, which can create confusions and irritations.

Sexual Instinct *Second* Compatibility

SX second individuals have the most balanced take on SX matters, and their most beneficial match could be someone just like them.

SX second people, as already mentioned before, tend to have the most balanced attitude regarding SX. They do not need help with it like SX first people, nor do they preferably not have to deal with it like SX last people; in fact, they’d prefer it if their partner wasn’t SX blindspot like them.

Besides that, they’d appreciate it like the other stackings if they were in a relationship with someone who is of the same flow and/or who soothes or matches their first instinct.

Best Matches

Following the above…

For So/Sx

  1. So/Sx
  2. Sx/So

*Possible exception/add-on: Healthy Sx/Sp individual.

For Sp/Sx

  1. Sp/Sx
  2. Sx/Sp

*Possible exception/add-on: Healthy Sx/So individual.

Worst Romantic Matches

Certain instinctual matches are simply too incompatible with each other for the long-term.

Following the above…

Sx/So + Sp/So

Sx/Sp + So/Sp

So/Sx + Sp/Sx

Why are they the worst?

First, opposite flows.

Secondly, even though they share the same secondary instinct, this commonality provides no benefits nor calming influence and is overshadowed by the threatening occupations of the other’s first instinct, which is the other’s blindspot.

What is one person’s neurotic obsession is the other’s least valued, and “falsely” flowing aspect.

Neither person values what the other is the most concerned with, nor can either one person help the other with their weak spots. No wonder their instinctual desires and hence their instinctual beings are the most opposite.

That is why I recommend people to avoid this kind of instinctual stacking match in dating (and close friendships). 

No matter how much the two may be infatuated with each other, the problems arising later in the long-term relationship are usually too difficult to resolve sensibly. Instinctual stackings do not change, so they are deeply embedded in someone’s psyche – trying to change someone’s flow or blindspot is a futile endeavor. 

Even if the people have a compatible intertype relation in Socionics, this intertype stacking match can have an underestimated, quite negative impact on their longterm happiness as a couple. If they learn to understand each other’s differences and if they have a very compatible ITR (at least 4 Stars), then it can still work with a lot of effort. Otherwise, the romantic relationship usually doesn’t even get started, and friendships usually grow apart.

Here the matches for each stacking, from most to least beneficial:

Sx/So: Sp/Sx > So/Sx > Sx/So > So/Sp or Sx/Sp Sp/So 
Sx/Sp: So/Sx > Sp/Sx > Sx/Sp > Sp/So or Sx/So > So/Sp

So/Sp: So/Sp > Sp/So > Sx/So or Sp/Sx > So/Sx Sx/Sp
Sp/So: Sp/So > So/Sp > Sx/Sp or So/Sx > Sp/Sx > Sx/So

So/Sx: So/Sx > Sx/So > Sp/So or Sx/Sp > So/Sp Sp/Sx
Sp/Sx > Sx/Sp > So/Sp or Sx/So > Sp/So > So/Sx

For dating and close friendships, I’d recommend people to focus on the stackings in the first two or three halves of the row.

  • An Sx/So individual should focus on Sp/Sx, So/Sx, Sx/So people.
  • An So/Sp individual should focus on So/Sp, Sp/So, Sx/So, Sp/Sx people.
  • An So/Sx individual should focus on So/Sx, Sx/So, Sp/So, Sx/Sp people.

Last update: 11th August 2021



  1. Good article~
    However, I think there is a mistake in the

    Here the matches for each stacking, from most to least ideal:

    So/Sx: Sp/So > Sx/So > So/Sx > Sx/Sp > So/Sp > Sp/Sx

    Sp/Sx: So/Sp > Sx/Sp > Sp/Sx > Sx/So > Sp/So > So/Sx

    I think it should be :

    So/Sx:  Sx/Sp > Sx/So > So/Sx > Sp/So > So/Sp > Sp/Sx

    Sp/Sx: Sx/So  > Sx/Sp > Sp/Sx > So/Sp > Sp/So > So/Sx



    • According to my logic there is no mistake, for as I said in the beginning – the ideal match “soothes” the neuroses of your first instinct. Sx/Sp is not ideal for So/Sx, because they are SO blindspot. That is not helpful to the SO of the So/Sx. And Sp/Sx does not get help with their SP with Sx/So who is SP blindspot. That is why for them, the other matches are more ideal.


  2. There is too much assumptions and too little tested.

    I’ve have read numerous of these assumptions stuff in the mbti community about relationships, while socionics is the first one to have figured it out for real. All the assumptions were found to be wrong.

    Theory should fit reality, not assumptions. Experiencing the relationships with stacking types, finding specific similarities and writing them down and finding a structure afterwards is better IMO.

    I’m currently in the proces of doing this.


    • It actually started out with experience.

      My parents, still married after many years: So/Sx + Sp/So

      Most married couples have been Sx/So+So/Sx, Sx/Sp+Sp/Sx, Sp/Sx+Sp/Sx, So/Sp+So/Sp.

      And many couples have been Sx/So + Sp/Sx, Sx/So + So/Sp.

      I think my theory fits reality and makes sense of it. The synflow/contraflow theory is mostly agreed upon. The “soothing” of the instincts is something I have discovered myself, but it makes sense to me, for the second instinct is the most “balanced” (not just my opinion), so it soothes any neuroses. And that explains why matches like Sx/Sp + Sp/Sx are so common.


  3. I’m sp/sx and my girlfriend is so/sx and we’re actually extremely compatible…. Perhaps more so than anyone I have ever known


  4. I’m intp Sx/sp in relationship almost 10 yrs with a Sx/so entj and it’s amazing , at first there was some conflict but wasn’t anything major and it only gets better with time .. I don’t understand how a Sp/so is better for me then a Sx /so .. I don’t think I have any friends with sexual last. I think many Sj types are Sp/so and I can hardly connect to them . I believe only when one persons dominant is the other persons repressed is causes real trouble ..


    • Many aspects go into compatibility, instincts are a big part, but other factors influence overall compatibility more. Actually, the INTP personality can get along well with SJs types because they both value Si, so you might actually be an Se valuing type.. which is either SP or NJ. And yeah it is true that Sx first people are typically best with someone who is not Sx last in a romantic relationship. But other than that, Sx last can be interesting and enriching for the stacking. Sp/So for Sx/Sp, … etc. Jungian type influences the dynamic in different ways… So there can be exceptions. But this article is about Enneagram instinctual compatibility alone, ignoring any other kinds of factors. You need to add everything together to get a full picture. I’ve typed an Sx/So-Sx/Sp couple before, and they do get along and have similar values, but also largely because they are both ISFP/have the same functions. The match is overall good, but technically the compatibility would be better if they were both in the same flow, e.g both Sx/So. He wants to change the social world, she wants to make her self-preservation products more mainstream, so that is where they go in opposite directions. it is a minute detail in the grand scheme, but in enneagram terms alone, it is a bit of a mismatch. assuming you both are correctly typed and indeed Sx/Sp and Sx/So, that won’t necessarily matter much if everything else matches (very) well.


  5. Hi Olimpia. Love your website and your content.

    Your theories regarding sx-doms and sx-seconds are intriguing (and make sense if one is to assume that two sx-doms together are very “double or bust” in regards to relationship success). However the obvious drawback is that the sp/sx or so/sx is potentially being forced to suffer a sub-par relationship with someone who in theory gets much more out of the relationship than they ever will (sx/so in the case of sp/sx and sx/sp in the case of so/sx). It comes across as quite lop-sided and I imagine more often than not the sx-second would be compelled to end the relationship either sooner or later.

    How does the sx-second find satisfaction in their respective relationship? Or should they stick to only the sx-first type which is in the opposite flow?



    • Hey Dick, happy to hear you enjoy the content!

      To some extent, which stacking is the “best” match for you depends on your personal priorities and preferences for a relationship. Overall, my general advice is that being in the same flow would be best, aka So/Sx+Sx/Sp+Sp/So and Sp/Sx+Sx/So+So/Sp, but the rest can vary.

      The Sx first with Sx second matches can seem quite lopsided in the same flow, but they have one key advantage of having all instincts present in the relationship. Especially when it comes to the Sp last stackings, whose lack of Sp focus can make them quite careless when it comes to “nesting”, building a family, security, relationship stability etc. That is where they will actually welcome someone like an Sp/Sx or Sx/Sp, who is creating that instinctual balance within the relationship. But ofc, if you don’t care about that, then another match is better.

      I talk more about that here:


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s