As recent surveys show, there are a lot of people who no longer see monogamy as their only option or their ideal relationship structure, especially among those who are still in their peak relationships-forming years.

With the interest in nonmonogamous relationship structures continuing to grow, it’s crucial that we better understand the spectrum of available options and organize them in a coherent way.

Most people think of nonmonogamy as something you do as a person who has at least one committed romantic partner (like those in open, polyamorous, or cheating relationships). However, unpartnered single people can and often are nonmonogamous as well.

A couple of weeks ago, we broke down the different options within partnered nonmonogamy. Today we’re going to look at our options within the unpartnered nonmonogamy parts of the relationships landscape.

To make our way through this part of the relationships landscape without getting lost, we need to clarify the distinctions between a few terms that greatly overlap: nonmonogamy, casual sex and dating, and singledom.

Curious about what type of relationship is best suited to you? Click here to take the LoveSmarter™ Ideal Relationship quiz…then keep an eye out for the follow-up email packed with deeper context about your results. 


Nonmonogamy is the practice of having multiple sexual and/or romantic partners concurrently or over a short period.

At its most basic, nonmonogamy can be divided into:

  • Partnered nonmonogamy refers to situations where an individual has at least one committed romantic partnership, along with additional sexual and/or romantic connections. This dynamic can take many forms, open monogamy and polyamory being the two most basic ones. Check out this post for an in-depth look into these.
  • Unpartnered nonmonogamy refers to scenarios where someone has multiple casual sexual or dating partners, but no long-term committed romantic partner – in other words, when one is single. 

Types Nm

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Casual Sex and Dating 

Broadly speaking: Casual sex is sex with someone you are not in a committed romantic relationship with.

By extension, casual dating is going out with someone on a relatively regular basis but without it having already progressed to a committed relationship, or without there being an intention of progressing it to a committed relationship.

A committed romantic relationship is one that involves mutual romantic love and care (attachment-based romance) and intention to maintain it over a longer period of time (commitment).

There are a few different dimensions along which to define casual sex/dating, and each dimension brings a somewhat different angle to it. It could be sex with/dating someone you:

  • Don’t know well;
  • Don’t have an emotional attachment to;
  • Are not currently in a committed relationship with;
  • Don’t intend to pursue a committed relationship with.

Each of these dimensions varies on a spectrum from not having it at all to having it to some extent but not to the level you’d have it with a committed partner, making some casual experiences much more casual than others.

For example, a stranger you picked up on the street whose name you don’t even know is more casual than an acquaintance you’ve seen around occasionally for a few years, who’s more casual than someone you’ve been close friends with for a few years who you’re now occasionally hooking up with, who’s more casual than an ex you were once in a committed relationship with but now only hooking up because the sex is still great.

Similarly, someone you have zero emotional attachment to is more casual than someone you have some emotional attachment to, who’s more casual than someone you have a lot of emotional attachment to.

These dimensions are somewhat distinct – so you could know someone very well (like a friend) but have no intention whatsoever of having a committed romantic relationship with them.

But they also often correlate to some extent, so typically a stranger you don’t know is also someone you don’t have any emotional attachment to, while a friend, an ex, or an ongoing lover is typically someone you have at least some emotional attachment to.

So overall, all these different dimensions combine together to create a spectrum of casualness that looks more or less something like this. 


(Given that this graph is trying to mush a few distinct dimensions together, it’s not going to ring exactly true in every single situation.
Think of it more as a general guideline rather than a firm rule.)

I like to think of this spectrum as divided into 3 general categories:

  1. On one end of the spectrum are the super casual, typically super short encounters where the focus is on novelty, quantity, and the thrill from not knowing how things could work out. These include:
    • one-night stands (sex with people you’re never going to have sex with again), or 
    • sex with strangers (sex with people you know very little about, even if you have sex with a few times).
  2. On the other end are the least casual, typically longer-term casual relationships, which try to maximize the quality of the experience through higher levels of familiarity, safety, and some level of emotional connection. These include:
    • Friends-with-benefits (people you occasionally also hook up with, but you’re also actual friends with and do other nonsexual things with, although have no intention of being in a committed romantic relationship with);
    • Ongoing lovers (people you have sex with most of the time you see each other, but also have some level of emotional, intellectual, and/or spiritual connection with);
    • Ex partners (people you used to be in a committed relationship with and still have some level of emotional attachment to, but are now only seeing for sex);
    • Casual dating partners, people you’re going out on a relatively regular basis but have no intention of progressing to a committed relationship.
  3. In between, there are the medium casual connections like:
    • Fuck buddies (people we have sex with regularly but without much emotional connection beyond the sexual), or
    • Short flings (people we hook up with intensely for a few days but are unlikely to see again, like while on vacation).

Each of these has somewhat different pros and cons, and will appeal to some people more than others. For example:

  • One-night stands with people you don’t know well are super novel and exciting. But the quality of the sex often disappoints and partners often show little respect or care for each other’s pleasure and well-being. (And the heavy substance use these often go together with doesn’t help the quality of the experience.)
  • Fuck-buddies can provide more consistent, decent sex that you don’t have to work for each time. But the lack of more meaningful intellectual or emotional connection can make things boring or empty as soon as the novelty wears off.
  • Ongoing friends-with-benefits,  lovers, exes, and casual dating partners often provide high-quality consistent sex, increased sense of safety, and emotional and/or intellectual nourishment. But unwanted one-sided feelings are easier to catch, and clear boundaries are harder to maintain. 

None of these are inherently better or worse than any of the others. It’s all about what you’re looking for in any given situation.

People can have any of the above forms of casual sex/dating if they are partnered and nonmonogamous. Though, given that most partnered people are monogamous (or at least try to be, at least most of the time), much of the casual sex and dating happens among people who are unpartnered (ie single). So let’s take a look at singledom.


Singledom is part of the relationship landscape that is defined by having no long-term committed romantic partner, but having one or more relatively casual sexual / dating partners.

(If someone doesn’t have any sexual or dating partners for prolonged periods of time, whether intentionally or unintentionally, they enter the relationship “country” of celibacy. What exactly is a “prolonged period of time” is an open question and somewhat subjective, but I’d put it at no less than 3 to 6 months of no sex or dating.)

Singledom (as well as celibacy) are often viewed as an inferior relationship status and greatly stigmatized in ways most of us (single or partnered) don’t even realize.

But the reality is a lot of people actively choose and are happy in singledom, whether temporarily or permanently.

A 2019 Pew Research Center survey of a representative sample of U.S. population found that 31% of U.S. adults were currently single. Half of those (15% of the total population) were not looking for any kind of committed or casual relationships. The other half were split between those looking for casual dates only (10%), committed relationships only (14%), or either (26%).

Meanwhile, a 2022 YouGov survey of a nationally representative sample of 1,195 U.S. adults population I conducted in collaboration with Ashley Madison, the world’s largest married dating site, found that:

  • 6% of women and 10% of men chose singledom as their ideal relationship type.
  • an additional 19% of women and 10% of men chose celibacy as their ideal.

Flavors of Singledom

Based on the way someone goes about their singledom, there are a few different flavors within this part of the relationship landscape.

Flavors Singledom

Based on the number of casual partners one has at a time, singledom can be done:

  1. Monogamously – having only one casual relationship at a time. This can take the form of:
    • an established casual partner (eg., a friend-with-benefits or a fuck buddy) with whom you are sexually exclusive for an extended period (e.g., a few months) before moving to other partners, or 
    • short-term serial dating, where you date one person at a time but for only a couple of weeks or months before starting to date someone else.
  2. Nonmonogamously – having multiple casual partners concurrently, over the same periods of time. This can take the form of any number of combinations of the different types of casual partners.

Some argue that all single people who are actively dating or having sex are effectively nonmonogamous, even if they are doing it sequentially, because of the relatively short period of time in between different partners and the typical lack of monogamous commitment to these partners. While this line of reasoning is not without theoretical merit, I think it’s more practically useful–and more reflective of people’s own experiences–to allow for more nuance within the different ways we can navigate singledom.

Based on the type of casual connections someone primarily goes for, singledom can be focused on pursuing:

  1. Short-term encounters, like one-night stands or short flings where the focus is on novelty, quantity, and the thrill from not knowing how things could work out;
  2. Ongoing casual connections, like fuck-buddies, friends-with-benefits, lovers, or exes; or
  3. Short-term casual dating partners, the folks we casually date for a couple of weeks or months but never progress to something more serious. 

Based on the frequency of sexual activity with different partners, singledom can be:

  • Super slutty, including very frequent pursuit of different partners;
  • Medium slutty, including occasional pursuit of different partners; or
  • A little slutty, including sporadic pursuits of different partners.

For the record, I use the term “slutty” in the most sex-positive way to refer to level of promiscuity, without any value-judgments attached to it. I myself have proudly been in the super slutty category for most of my life, so I wholeheartedly embrace the beauty and power of that term.

Based on the amount of time people remain single, singledom can be:

  • Temporary, when people see their singledom as a temporary phase or set of phases before entering a committed relationship or between committed relationships. 
  • Long-term, when people have a long-term commitment to staying uncommitted.

Finally, based on the level of awareness different partners have about each other, singledom can range on a spectrum:

  • Undisclosed, when different partners have no awareness or knowledge of any other partners they may have or are pursuing. 
  • Don’t-Ask-Don’t-Tell” (DADT), when there has been some explicit acknowledgment or indication that the casual partners have or are pursuing other partners, but the specifics of these other partners are not discussed. 
  • Disclosed, when casual partners share some more specific information about the other partners they have or are pursuing. 

The Pros and Cons of Singledom 

Like any relationship structure, singledom has some unique benefits and some unique challenges, and will be a great fit for some people (at least some of the time) and a poor fit for other people.

One one hand, singledom allows for a lot of freedom and independence to enjoy sexual pleasure and intimacy with multiple people, as well as other non-sexual pursuits, without the constraints, compromises, and complexities imposed by romantic relationships.

On the other hand, singledom lacks the built-in day-to-day social, emotional, and logistical support that partnered relationship structures provide, and thus requires a more concerted effort to seek out and maintain high-quality sexual and nonsexual connections to prevent loneliness and isolation. 

How do you figure out which relationship type is right for you? Take the LoveSmarter™ Ideal Relationship quiz and keep an eye out for the follow-up email packed with deeper context about your results!


Interested in learning more about the single life? Here are a few books I highly recommend: