Attachment Styles and Infidelity: What Research Does—and Does Not—Show

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Author: Ukrainian Psychological Hub · Published: September 27, 2026 · Editorial Policy

Attachment styles are associated with infidelity in research, but the relationship is probabilistic, modest, and highly context-dependent. The strongest synthesis currently available—a systematic review and meta-analysis of 17 studies involving 13,666 participants—found small positive associations between both attachment anxiety and attachment avoidance and marital infidelity. Those findings matter. They do not mean that insecurely attached people are destined to cheat, that securely attached people do not cheat, or that an affair reveals a person's attachment style.

Attachment is one layer in a much larger system. A systematic review of 82 quantitative studies on factors associated with infidelity found evidence across individual, relationship, and contextual levels. Commitment, relationship quality, attitudes, opportunity, sexuality, culture, and other variables can matter alongside attachment. The same behavior can arise through different pathways in different people.

This article owns one narrow question: what does research actually show about attachment styles and infidelity? For the broader question of what counts as infidelity, see What Is Infidelity? Meaning, Types, Examples, and What Research Shows. For the wider evidence on motives, opportunity, relationship factors, and other correlates, see Why Do People Cheat? Motives, Opportunity, Relationship Factors, and Research.

The Short Answer: Are Attachment Styles Linked to Infidelity?

Yes, at the group level. The best current meta-analytic evidence suggests that higher attachment anxiety and higher attachment avoidance are each associated with somewhat higher rates of infidelity. In the dimensional analyses reported by Ghiasi and colleagues, the weighted correlations were about r = .19 for attachment anxiety and r = .19 for attachment avoidance. These are small associations, not strong individual predictions.

The same meta-analysis also examined categorical attachment labels in a subset of studies. Dismissive attachment showed a small positive association with infidelity, fearful attachment showed a somewhat larger but still modest association, and preoccupied attachment was not statistically significant in the pooled categorical analysis. Because attachment categories and dimensions are measured differently, those results should not be treated as interchangeable rankings of who is 'most likely' to cheat.

The scientifically useful conclusion is therefore narrower than the popular one: attachment insecurity can be one correlate of infidelity risk, and different attachment-related processes may help explain some people's vulnerability to outside relationships. Attachment style cannot identify a cheater, prove motive, or excuse a decision to violate a relationship agreement.

What “Attachment Style” Means in This Research

Most contemporary adult romantic attachment research is organized around two dimensions: attachment anxiety and attachment avoidance. Anxiety concerns fears of rejection or abandonment and heightened concern about a partner's availability. Avoidance concerns discomfort with dependence, closeness, or relying on a partner. Lower levels of both dimensions are commonly described as greater security.

The four familiar labels—secure, anxious or preoccupied, dismissive-avoidant, and fearful-avoidant—are useful summaries of positions on those dimensions, but they are not psychiatric diagnoses or fixed personality types. For the full model, measurement issues, and terminology, see Attachment Styles in Adults: The Four Patterns, Two Dimensions, and What They Mean and Adult Attachment Theory: How Anxiety and Avoidance Shape Relationships.

That distinction is especially important for infidelity research. A person can score relatively high on avoidance without fitting an internet stereotype of an 'avoidant partner.' A person can score high on anxiety without constantly seeking reassurance. Attachment scores describe tendencies in relationship-related emotion, cognition, and behavior; they do not function as forensic tools for explaining one act.

What the Meta-Analysis Actually Found

Ghiasi and colleagues searched major databases through April 2023 and included 17 peer-reviewed studies with a combined sample of 13,666 participants. The studies used several adult attachment measures, including dimensional measures of anxiety and avoidance and categorical measures that classify secure, preoccupied, dismissive, or fearful patterns.

Across the dimensional studies, higher anxiety and higher avoidance were each associated with more infidelity. The pooled correlations were small: about .19 for anxiety and .19 for avoidance. In the categorical analyses, dismissive attachment had a pooled association around r = .08 and fearful attachment around r = .14; the preoccupied category was not significant in the reported pooled analysis. The paper's abstract presents a combined insecurity estimate of about r = .18.

A small correlation can be statistically reliable and still have limited power for judging an individual. People high in attachment anxiety or avoidance include many who do not cheat. People low in insecurity include some who do. The distributions overlap substantially.

The review also found important heterogeneity among studies, including high heterogeneity in some analyses. Samples, relationship status, attachment measures, and operational definitions of infidelity differed. That variability is one reason the pooled result is best understood as evidence of association rather than a universal behavioral rule.

Avoidant Attachment and Infidelity: Why the Link Is Plausible but Not Destiny

Avoidant attachment has received particular attention because one plausible pathway runs through commitment and attention to alternatives. In eight studies by DeWall and colleagues, higher dispositional attachment avoidance was associated with more permissive attitudes toward infidelity, greater attention or interest in attractive alternatives, more positive evaluations of alternatives, and more infidelity over time in several studies. In Studies 5 through 8, lower relationship commitment statistically mediated the association between avoidance and the outcomes the researchers examined.

That series is stronger than a single cross-sectional survey because it used multiple methods and included longitudinal outcomes. Even so, mediation in these designs should not be translated into a universal causal story. 'Avoidance causes low commitment, which causes cheating' is more definitive than the evidence warrants. Commitment is one possible pathway among many, and attachment avoidance does not remove agency.

Marriage data also complicate a simple avoidant-equals-cheating narrative. Russell, Baker, and McNulty followed 207 newlywed marriages across two longitudinal studies. In those samples, attachment anxiety showed actor–partner patterns related to infidelity, while a person's own attachment avoidance was not positively associated with infidelity in the straightforward way seen in some dating research. The authors explicitly questioned whether findings from dating samples can simply be generalized to marriage.

More recent evidence adds another piece rather than settling the issue. Coyle and colleagues studied 584 adults, with 553 included in the reported mediation analysis and found that adverse childhood experiences were associated with both anxious and avoidant attachment, but only avoidance was positively associated with cheating frequency and statistically mediated the ACE–infidelity association. Because this was based on self-report data and mediation analysis, the result supports a possible pathway; it does not demonstrate that childhood adversity produces avoidance and then causes infidelity in a fixed sequence.

The practical takeaway is not that an avoidant attachment style predicts betrayal. It is that avoidance may be relevant in some cases through lower commitment, greater psychological distance, or greater openness to alternatives. Whether any of those processes applies to a specific person requires evidence about that person's behavior and relationship, not a label.

Anxious Attachment and Infidelity: The Paradox of Fearing Abandonment

Attachment anxiety can look paradoxical in this context. If someone strongly fears abandonment, why engage in behavior that could end the relationship? The empirical answer is that anxious attachment is associated with infidelity in some studies, but the mechanisms appear to vary.

The Ghiasi meta-analysis found a small positive pooled association between attachment anxiety and infidelity. Russell and colleagues also found that anxiety mattered in newlywed marriages, but their results were dyadic: combinations of a person's own anxiety and a partner's anxiety were relevant. That is a reminder that couple processes cannot always be reduced to one person's style.

One proposed pathway involves fear of being single. In an online community sample of 233 adults, Sakman, Urganci, and Sevi found that higher attachment anxiety was associated with greater fear of being single, which in turn was associated with more self-reported infidelity behavior. The statistical mediation held after controlling for sex, age, and relationship length.

This finding is psychologically coherent: someone who is highly sensitive to abandonment might seek reassurance, validation, or a perceived 'backup' relationship. But the study was cross-sectional and based on self-report, so it cannot establish a causal chain from anxiety to fear of being single to infidelity. It identifies one plausible mechanism that requires replication and longitudinal testing.

A person with an anxious attachment style is therefore not inherently more disloyal, dependent, manipulative, or likely to cheat. Attachment anxiety describes a pattern of relationship-related insecurity; it does not determine moral choices or behavior.

What About Secure and Fearful-Avoidant Attachment?

Secure attachment

Lower anxiety and lower avoidance—greater attachment security—are associated with lower infidelity rates in the aggregate literature. That does not make secure attachment a guarantee of fidelity. Infidelity is multiply determined, and people with relatively secure attachment can still encounter attraction, opportunity, dissatisfaction, changing commitments, or motives unrelated to attachment.

The useful way to read secure attachment in this literature is as one relational tendency among many. Security may be associated with processes that support commitment and relationship maintenance, but a security label is not a character certificate.

Fearful-avoidant attachment

Fearful-avoidant attachment combines relatively high anxiety with relatively high avoidance. In the categorical portion of the Ghiasi meta-analysis, fearful attachment was positively associated with infidelity. That finding fits a pattern in which desire for closeness and fear or discomfort around closeness can coexist.

Older work by Allen and Baucom helps show why frequency alone is too crude. Among people who reported prior extradyadic involvement, fearful and preoccupied patterns were associated with more intimacy-related motives, while dismissive attachment was associated with more autonomy-related motives. Fearful participants also reported more ambivalence about intimacy in the outside relationship. Dismissive participants did not simply report more casual extradyadic involvement across the board.

So even when attachment is related to infidelity, it may be related to the meaning, motive, or pattern of the outside involvement rather than merely to whether infidelity occurred. For the broader high-anxiety/high-avoidance construct, see Fearful-Avoidant Attachment Style: Signs, Triggers, and the High-Anxiety High-Avoidance Pattern.

A September 2026 Study Adds Fresh Evidence—Without Changing the Core Conclusion

A September 2026 study in the Journal of Sex & Marital Therapy examined attachment insecurity alongside marital satisfaction, relationship commitment, attitudes toward infidelity, and infidelity. The authors reported positive associations between anxious and avoidant attachment strategies and infidelity, while higher marital satisfaction and commitment were negatively associated with infidelity. Their mediation analyses placed attachment insecurity within a broader set of psychological pathways.

This is useful fresh evidence because it tests attachment alongside other relationship variables rather than in isolation. It is still one study, published ahead of print, and its mediation model does not by itself establish causal order. The broader evidence remains most consistent with a multivariable model: attachment matters for some people and contexts, but it does not operate alone.

Why Studies Can Reach Different Conclusions

Dating and marriage are different research contexts

A college dating sample, a newlywed marriage sample, and a community sample of adults with prior affairs are not interchangeable. Commitment structures, opportunities, cohabitation, children, finances, relationship duration, and norms of exclusivity can differ substantially. Russell and colleagues' marriage findings are an explicit example of why results from dating studies should not be assumed to transfer unchanged to marriage.

Dimensions and categories are not the same measurement model

Studies that measure anxiety and avoidance continuously can detect gradients that a four-category classification may obscure. A participant near a category boundary may look categorically different from another participant while being very similar dimensionally. This helps explain why pooled anxiety results and pooled 'preoccupied style' results can differ.

Infidelity itself is measured in different ways

Some studies ask about sexual intercourse outside a relationship. Others include emotional involvement, kissing, online behavior, secrecy, or broader extradyadic activity. Some measure lifetime history; others measure behavior during a current relationship or over a follow-up period. Those outcomes are related but not identical.

The Hub therefore keeps the broad definition and forms of infidelity with the infidelity pillar rather than treating every study's operational definition as universal.

Self-report creates unavoidable uncertainty

Infidelity is private, stigmatized behavior. Most studies rely on participants to disclose both relationship behavior and psychological tendencies accurately. Recall, social desirability, differing personal definitions of cheating, and selective participation can influence results. Anonymous research reduces some pressure but does not eliminate measurement error.

Partner effects matter

Attachment exists inside relationships, not only inside isolated individuals. One partner's anxiety or avoidance may interact with the other partner's attachment, responsiveness, commitment, conflict behavior, or relationship expectations. Actor–partner findings in newlywed research illustrate why 'What is the cheater's style?' can be an overly narrow question.

Possible Mechanisms: What Researchers Have Proposed

Lower commitment and greater attention to alternatives

The best-developed mechanism for avoidance is lower commitment paired with greater interest in alternatives. DeWall and colleagues repeatedly found evidence consistent with this pathway. It is a statistical explanation of part of an association, not a moral explanation and not a complete account of infidelity.

Fear of abandonment and fear of being single

For attachment anxiety, fear of abandonment may sometimes coexist with efforts to secure reassurance or preserve access to a relationship. The Sakman study's fear-of-being-single pathway is one empirical model of how that paradox might operate. Other anxiously attached people may respond to insecurity in entirely different ways.

Intimacy, autonomy, and self-esteem motives

Allen and Baucom's work suggests that attachment pattern can be associated with the motives people describe for extradyadic involvement. Fearful and preoccupied participants more often reported intimacy-related motives in their samples, whereas dismissive participants more often reported autonomy motives. These patterns show that two people can both be unfaithful for psychologically different reasons.

Broader relationship and contextual conditions

Attachment should not crowd out other evidence. The systematic review by Haseli and colleagues found that infidelity correlates span individual, couple, and social/contextual domains. Opportunity, commitment, relationship dissatisfaction, attitudes toward infidelity, sexual variables, and demographic or cultural factors can all enter the picture.

For that broader map, the appropriate owner is Why Do People Cheat? Motives, Opportunity, Relationship Factors, and Research. INF-15 keeps the attachment evidence in focus rather than turning attachment into a theory of every affair.

Attachment Is an Explanation Framework, Not an Excuse

Attachment language is often used after betrayal to convert a painful event into a simple story: 'He cheated because he is avoidant,' 'She needed validation because she is anxious,' or 'A secure person would never do this.' Research does not justify those conclusions.

An attachment-related vulnerability can help explain why a situation felt threatening, why alternatives became salient, or why commitment weakened. It does not decide the behavior. Relationship agreements are still agreements, and infidelity involves choices within a context.

This distinction also protects against misplaced blame. If one partner cheats, the betrayed partner's attachment style does not become a causal explanation for the other person's decision. Couple dynamics can influence relationship satisfaction and conflict; they do not automatically transfer responsibility for secret or agreement-violating behavior.

Can Attachment Style Predict Who Will Cheat?

Not with the precision implied by that question. Group-level correlations can tell researchers that risk differs on average. They cannot turn an attachment questionnaire into a prediction tool for individual fidelity.

The meta-analytic effects are modest, study populations vary, and infidelity has many associated factors. A person's current behavior, explicit agreements, honesty, commitment, opportunities, values, and relationship context are more directly relevant to understanding a specific situation than assigning a style label.

There is also no validated clinical rule that says a particular attachment score means someone will cheat. Attachment style is not a DSM or ICD diagnosis, and infidelity itself is not a mental disorder.

Does Cheating Prove Someone Is Avoidantly Attached?

No. Cheating is a behavior; avoidant attachment is a pattern measured through relationship-related anxiety and avoidance constructs. One does not diagnose the other.

Someone may cheat while having low attachment avoidance. Someone may be highly avoidant and remain faithful throughout a relationship. Someone may show avoidance only in a particular relationship or during a particular period. Inferring attachment style backward from an affair is a classic example of treating an association as an identity.

Does Anxious Attachment Mean Someone Cheats for Reassurance?

It can be one hypothesis in some cases, not a general rule. Research links attachment anxiety with infidelity at the group level, and one study found a statistical pathway through fear of being single. That does not mean all anxiously attached people seek backup partners, crave outside validation, or respond to abandonment fears by cheating.

If reassurance, validation, or fear of being alone was actually part of an affair, that conclusion should come from the person's reported motives and behavior rather than from the attachment label alone.

How Attachment Evidence Can Be Used in Therapy or Reflection

Attachment can be clinically useful when it is treated as a formulation tool rather than a verdict. A therapist or couple might explore whether fear of abandonment, discomfort with dependence, difficulty tolerating closeness, low commitment, attention to alternatives, or conflicting needs for autonomy and intimacy were relevant to the relationship.

Those questions can generate hypotheses about patterns that deserve attention. They should be tested against the couple's actual history. Therapy should not begin with the assumption that an attachment label explains the affair, and no attachment formulation guarantees reconciliation, forgiveness, renewed trust, or relationship survival.

When the issue is infidelity, accountability for concrete behavior and clarity about relationship agreements remain distinct from attachment work. Attachment language is most useful when it improves understanding without replacing facts.

What the Evidence Supports—and What It Does Not

The evidence supports a modest association between attachment insecurity and infidelity, with both anxiety and avoidance implicated in the current meta-analysis. It supports plausible pathways involving commitment and alternatives for avoidance, and it offers preliminary pathways involving fear of being single for anxiety. It also shows that attachment may be related to the motives and pattern of extradyadic involvement.

The evidence does not support a ranking system that identifies which attachment style 'cheats most' across all populations. It does not support diagnosing attachment style from an affair. It does not show that insecure attachment causes infidelity in every person, that secure attachment prevents it, or that attachment explains away responsibility.

The strongest reading is also the most useful one: attachment is one probabilistic layer in a multilevel phenomenon. It can sharpen questions. It cannot substitute for the person's choices, the couple's agreements, or the wider relationship and social context.

Frequently Asked Questions

Which attachment style is most likely to cheat?

Research does not support a single universal 'most likely' style. The 2024 meta-analysis found similar small positive pooled correlations for attachment anxiety and avoidance when measured dimensionally. Categorical findings differed: dismissive and fearful styles were positively associated, while the preoccupied category was not significant in the pooled analysis. Different samples and measures produce different patterns.

Do avoidant people cheat more?

Higher attachment avoidance is associated with more infidelity in the pooled literature and in several individual studies. DeWall and colleagues also found links through lower commitment and greater interest in alternatives. But marriage research has not always found the same actor effect, and many highly avoidant people do not cheat.

Does anxious attachment cause cheating?

No causal conclusion is justified. Attachment anxiety is positively associated with infidelity in the meta-analysis. One cross-sectional study found a statistical pathway through fear of being single, and newlywed studies found anxiety-related actor–partner patterns. These findings establish association and plausible mechanisms, not inevitable causation.

Are securely attached people less likely to cheat?

Lower attachment anxiety and avoidance are associated with lower infidelity rates on average. That is compatible with lower risk among more secure people, but security does not guarantee fidelity and should not be used as proof that someone would never cheat.

Does cheating mean someone has an attachment disorder?

No. Adult romantic attachment insecurity is not an 'attachment disorder,' and infidelity is not evidence of a psychiatric diagnosis. Adult attachment styles are relationship-research constructs. Clinical attachment disorders are separate diagnostic concepts and should not be inferred from relationship behavior.

Can attachment style explain serial cheating?

Attachment may be one relevant variable, but repeated infidelity cannot be reduced to attachment style. Repetition can involve commitment, opportunity, attitudes, sexual motivations, deception patterns, relationship context, and other individual differences. A style label is not a sufficient explanation.

Should couples focus on attachment after infidelity?

Attachment can be worth exploring when it maps onto the couple's actual patterns, especially around abandonment fears, distance, autonomy, closeness, commitment, and attention to alternatives. It should be one part of a broader assessment, not the assumed cause of the affair.

References

Allen, E. S., & Baucom, D. H. (2004). Adult attachment and patterns of extradyadic involvement. Family Process, 43(4), 467–488. https://doi.org/10.1111/j.1545-5300.2004.00035.x

Coyle, P., Van Doorn, G., Teese, R., & Dye, J. (2025). Adverse childhood experiences and infidelity: The mediating roles of anxious and avoidant attachment styles. Family Process, 64(1), e13088. https://doi.org/10.1111/famp.13088

DeWall, C. N., Lambert, N. M., Slotter, E. B., Pond, R. S., Jr., Deckman, T., Finkel, E. J., Luchies, L. B., & Fincham, F. D. (2011). So far away from one's partner, yet so close to romantic alternatives: Avoidant attachment, interest in alternatives, and infidelity. Journal of Personality and Social Psychology, 101(6), 1302–1316. https://doi.org/10.1037/a0025497

Ghiasi, N., Rasoal, D., Haseli, A., & Feli, R. (2024). The interplay of attachment styles and marital infidelity: A systematic review and meta-analysis. Heliyon, 10(1), e23261. https://doi.org/10.1016/j.heliyon.2023.e23261

Haseli, A., Shariati, M., Nazari, A. M., Keramat, A., & Emamian, M. H. (2019). Infidelity and its associated factors: A systematic review. The Journal of Sexual Medicine, 16(8), 1155–1169. https://doi.org/10.1016/j.jsxm.2019.04.011

Iftikhar, I., & Malik, S. (2026). Attachment insecurity and infidelity in marriage: Psychological pathways and clinical implications. Journal of Sex & Marital Therapy. Advance online publication. https://doi.org/10.1080/0092623X.2026.2725777

Russell, V. M., Baker, L. R., & McNulty, J. K. (2013). Attachment insecurity and infidelity in marriage: Do studies of dating relationships really inform us about marriage? Journal of Family Psychology, 27(2), 242–251. https://doi.org/10.1037/a0032118

Sakman, E., Urganci, B., & Sevi, B. (2021). Your cheating heart is just afraid of ending up alone: Fear of being single mediates the relationship between attachment anxiety and infidelity. Personality and Individual Differences, 168, 110366. https://doi.org/10.1016/j.paid.2020.110366

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