Intolerance Of Uncertainty

Intolerance of uncertainty (IU) refers to a tendency to react negatively to uncertain situations or events. IU can be understood as the idea that people need guarantees in life and may struggle to cope with unpredictability.

People with a high intolerance of uncertainty may experience distress at the possibility of a negative event occurring. They may find possible future negative events unacceptable and threatening even if the event is unlikely to happen.

IU is triggered by not-knowing, not by risk size. A person high in IU can find a small, unlikely problem just as distressing as a large one, because the discomfort comes from the uncertainty rather than the odds.

IU began in worry research. It was first studied as a driver of chronic worry and generalized anxiety disorder, and has since been linked to OCD, social anxiety, panic disorder, depression and autism.

As psychologist R. Nicholas Carleton has argued, IU may be something deeper still: a “fear of the unknown” that underlies anxiety more broadly (Carleton, 2016).

Many people may have experienced intolerance of uncertainty during the COVID-19 pandemic, at a time when everything felt uncertain.

A Real-World Example

Mark is an office worker who worked remotely during the pandemic. When his company announces a gradual return to the office, Mark becomes extremely anxious. He obsessively checks news sites and health authority websites multiple times a day for updates on case numbers and safety guidelines. 

He feels trapped. 

Despite the company's safety measures, Mark has trouble sleeping due to constant worry about potential exposure. He frequently emails his manager asking for more details about the office reopening plan and becomes visibly distressed when they can't provide exact dates or specifics. 

Mark starts avoiding errands. He declines socially distanced meetups with friends, preferring to stay home where he feels more in control of his environment and potential exposure risks.

It is normal to feel uncertain about certain things at times, but it can become a problem when it interferes with many aspects of a person’s life.

Signs of someone with high intolerance of uncertainty

Below are some signs that someone may have a high tolerance of uncertainty:

Discomfort With The Unknown

People with intolerance of uncertainty often find it difficult to cope with the possibility of negative events occurring, even if the chances of those events happening are slim.

They may have a strong need for predictability and guarantees in life and can become distressed when faced with ambiguity.

IU can drive excessive worry about uncontrollable things. For example, someone with high IU might worry excessively about the weather, or a loved one getting sick.

Misinterpreting things as threatening

Individuals who find it difficult to tolerate uncertainty may misinterpret ambiguous information, often perceiving it as more threatening than it actually is.

This can manifest as a tendency to catastrophize, imagining worst-case scenarios in situations where the actual level of risk is low.

A noise at night could trigger this. For example, a person with high IU might immediately assume it is an intruder, even when a more likely explanation exists, and become very anxious.

Certainty-Seeking Behaviours

A key sign of intolerance of uncertainty is engaging in excessive certainty-seeking behaviors in an attempt to alleviate anxiety and gain a sense of control. This can include behaviors such as:

• Reassurance Seeking: Frequently asking others for reassurance that everything is okay or that a negative event won’t happen. For instance, they might constantly ask their partner for reassurance that they’re still loved.
• Checking: Repeatedly checking things, such as locks, appliances, or homework, to make sure they are correct and to prevent a negative outcome. This can be time-consuming and interfere with daily life.
• Excessive Information Seeking: Spending an excessive amount of time researching information, often online, in an attempt to eliminate any possibility of uncertainty or risk. For example, a person worried about their health may spend hours researching symptoms online, even if their doctor has reassured them that they are fine.

These behaviors can provide temporary relief from anxiety but ultimately serve to reinforce negative beliefs about uncertainty and maintain the cycle of intolerance.

Psychologists call these safety behaviors. Each act of checking or reassurance-seeking briefly lowers anxiety, but it also confirms the belief that uncertainty is dangerous, so the underlying intolerance is strengthened rather than resolved.

Needing to be in Control

A need for control is a common characteristic of individuals with high IU. This need for control may stem from a desire to manage distress and reduce anxiety provoked by uncertainty.

When individuals feel a lack of control over situations with potentially negative outcomes, their IU is activated, leading to anxiety and distress.

Travel planning is a common example. Someone with high IU may want full control over every detail of the trip. They might check every option for the best deal, hold onto the passports, and double- and triple-check their packing, rather than trusting anyone else.

Difficulty with Decision Making

Individuals with high intolerance of uncertainty often struggle with decision-making, especially when faced with choices that have unclear outcomes.

This difficulty stems from a fear of making the “wrong” choice and a desire for guaranteed positive results.

Psychologists call this pattern inhibitory IU: when doubt is severe enough, it can freeze action altogether rather than just prompting extra checking or planning.

People with IU may:

• Spend excessive time weighing options
• Constantly seek additional information before deciding
• Feel paralyzed when faced with multiple choices
• Frequently second-guess decisions after they’re made

For example, someone with a high IU may extensively research college majors but, despite this, cannot commit to a decision. They may worry about job prospects, potential regrets, and whether they’ll enjoy the coursework.

This indecision causes them significant stress and anxiety, leading them to consider delaying college altogether rather than risk making the “wrong” choice.

Procrastination and Avoidance

Procrastination and avoidance may be common, particularly when certainty-seeking behaviors are not possible or perceived as ineffective.

These behaviors serve as a defense mechanism to minimize potential distress and anxiety caused by the anticipation of uncertainty.

• Procrastination allows individuals to delay engaging in tasks with uncertain outcomes, thereby temporarily avoiding the anxiety caused by IU. For example, a student might procrastinate on a challenging assignment because they fear receiving a bad grade, reflecting their inability to tolerate the uncertainty of the outcome
• Avoidance involves steering clear of situations or activities that could lead to uncertainty or ambiguity. This could mean declining social invitations due to a fear of awkward silences or avoiding trying new things for fear of failure. For instance, if someone fears not knowing what to say in social situations, they might avoid social gatherings altogether.

Intolerance of Uncertainty in Other Conditions

Intolerance of uncertainty can be present in many mental health and other conditions:

This pattern is not just anecdotal. A meta-analysis pooling 181 studies and over 52,000 participants found a moderate, reliable association between IU and symptoms across every disorder examined (McEvoy et al., 2019). The authors called this “definitive evidence” that IU is a genuinely transdiagnostic vulnerability.

Generalized Anxiety Disorder (GAD)

Intolerance of uncertainty is considered a significant risk factor for GAD. In GAD, IU often fuels excessive and uncontrollable worry. The inability to tolerate uncertainty about everyday events and potential negative outcomes leads to persistent anxiety and apprehension.

For instance, someone with GAD might constantly worry about their finances, relationships, or health, even in the absence of concrete reasons for concern. This stems from their need to predict and control the future, driven by the fear of unexpected negative events.

Their intolerance of not knowing “for sure” drives the need for constant reassurance and attempts to control situations with inherently uncertain outcomes.

Researchers have traced why IU fuels GAD so strongly. In an early controlled study, intolerance of uncertainty was the strongest factor separating GAD patients from non-anxious adults, ahead of related beliefs about worry (Dugas et al., 1998).

A larger 2026 meta-analysis of 115 studies and over 28,000 participants confirmed this pattern is strongest for GAD, and weaker for panic disorder and OCD (Akbari et al., 2026).

Obsessive-Compulsive Disorder (OCD)

There is a strong link between IU and OCD, particularly regarding specific symptom dimensions like contamination and unacceptable thoughts.

This link is not uniform across OCD. It is strongest for checking, contamination and unacceptable-thoughts presentations specifically, rather than OCD as a whole (Pinciotti et al., 2021).

In these cases, the need for certainty drives compulsive behaviors and rituals aimed at neutralizing the anxiety provoked by uncertainty.

• Contamination Fears: People with contamination fears might engage in excessive cleaning, handwashing, or avoidance of perceived contaminants to manage the uncertainty and anxiety around potential illness. The act of performing these rituals provides a temporary sense of control and certainty, reinforcing the behavior despite its irrationality.
• Unacceptable Thoughts: Individuals troubled by intrusive, unwanted thoughts in OCD may engage in mental rituals, checking behaviors, or reassurance-seeking to alleviate the distress caused by these thoughts. Their IU makes it difficult to dismiss these thoughts as insignificant, leading to a perpetual cycle of anxiety and compulsive behaviors aimed at finding certainty and relief.

The urge to quickly act on distress seems to strengthen the link between uncertainty-related distress and OCD symptoms, especially compulsions like checking or washing and obsessive thoughts.

Social Anxiety Disorder (SAD)

IU plays a crucial role in social anxiety, where individuals fear negative evaluation and uncertainty in social situations.

Those with high IU tend to interpret ambiguous social cues negatively, leading to increased anxiety and avoidance of social interactions.

For example, someone with SAD might avoid social gatherings due to the uncertainty of conversation topics, fear of awkward silences, or the possibility of saying the wrong thing.

This avoidance may stem from their inability to tolerate the lack of control and predictability in social settings.

Panic Disorder (PD)

IU may significantly influence panic disorder, particularly concerning the uncertainty surrounding panic attacks.

Not knowing when it will strike is unsettling. So is the perceived lack of control during an attack, and the uncertainty about when the next one will happen.

For example, someone with PD might fear physical sensations like a racing heart or shortness of breath. They may interpret these catastrophically. A racing heart can feel like the start of a heart attack, or a sign they are losing control.

The inability to tolerate the uncertainty surrounding these physical sensations fuels the panic cycle, leading to avoidance of situations or activities perceived as potential triggers.

Autism

Autistic individuals often experience heightened anxiety in situations of uncertainty, which can be observed in various ways:

• Increased Anxiety and Distress: Autistic individuals often exhibit higher levels of anxiety and distress when faced with unexpected events or changes in routine. This heightened anxiety can make it challenging for them to cope with novel or unpredictable situations.
• Insistence on Sameness and Routine: The need for predictability and control associated with IU often manifests as a strong preference for sameness and adherence to routines. This can involve seeking predictable environments and resisting changes to established patterns.
• Repetitive Behaviours: Engaging in repetitive behaviors, a common characteristic of autism, can serve as a coping mechanism to manage anxiety and uncertainty. These behaviors can offer a sense of predictability and control in otherwise unpredictable situations.
• Social Challenges: IU can exacerbate social challenges in autistic individuals. The unpredictability of social interactions and difficulty understanding social cues can heighten anxiety and lead to avoidance of social situations.
• Sensory Sensitivities: Autistic individuals may exhibit sensory sensitivities that are further amplified by uncertainty. The inability to anticipate or control sensory input in unfamiliar environments can be overwhelming and contribute to anxiety.

How to manage intolerance of uncertainty

Below are some helpful tips for managing intolerance of uncertainty. You may need to try different approaches to find what works best for you.

If you are struggling with intolerance of uncertainty, it may be beneficial to seek guidance from a mental health professional.

They can provide personalized support. They also teach specific techniques, such as cognitive restructuring and exposure therapy, to address the underlying causes of your anxiety and help you manage your reactions to uncertainty.

A group-based version of this therapy has shown lasting benefits, with patients continuing to improve for two years after treatment ended (Dugas et al., 2003).

Challenge the Need for Certainty

Many people with anxiety believe that they need certainty to be happy. This can lead to behaviors like excessive checking, reassurance-seeking, and avoidance of uncertain situations.

It is important to challenge this belief by asking yourself questions, such as:

• What are the advantages and disadvantages of needing certainty?
• Can I be absolutely certain about everything?
• How likely are the things I predict to actually happen?
• Are there any uncertainties in life that you are capable of living with?

These questions can help you see that trying to eliminate uncertainty is impossible.

Focus on the Present

It is helpful to shift your focus to the present moment rather than dwelling on uncertainties about the future.

When you find yourself worrying about things you cannot control, try practicing mindfulness or engaging in activities you enjoy.

Focusing on what you can control in the present can help reduce anxiety.

A simple mindfulness tip is the “5-4-3-2-1” grounding technique. Start with your senses. Identify 5 things you can see, 4 you can touch, 3 you can hear, 2 you can smell, and 1 you can taste.

Become Aware of Your Need for Certainty

Pay attention to the situations and thoughts that trigger your need for certainty. Notice how you feel physically and emotionally when you feel uncertain.

By becoming more aware of your reactions to uncertainty, you can start to interrupt automatic thought patterns and develop more helpful coping mechanisms.

Don’t Respond to the Need for Certainty

When you feel the urge to seek certainty, try to resist engaging in unhelpful behaviors such as checking or reassurance-seeking.

These behaviors can feel temporarily relieving but ultimately reinforce intolerance of uncertainty. Instead of giving in to the urge, try to sit with the uncomfortable feelings and observe them without judgment.

Try “urge surfing.” Picture the urge to check or seek reassurance as a wave: it rises, peaks, and passes on its own if you do not act on it. Focus on your breath as you let it pass.

Accept Uncertainty

Accepting uncertainty is a process of letting go of the need to control everything and acknowledging that uncertainty is a normal part of life.

It is about developing the willingness to tolerate uncertainty and embracing the unknown. Remember that even without guarantees, you can still live a full and meaningful life.

When you notice yourself needing certainty, pause and say to yourself: “I’m noticing my need for certainty right now.”

Then, choose not to respond to this need by worrying. Instead, tell yourself, “Uncertainty is just a part of life. I’ll let my need for certainty go.”

Visualize your need for certainty floating away like clouds in the sky. Finally, refocus on the present moment by paying attention to your breathing or the physical sensations in your body.

If your mind wanders back to needing certainty, gently bring your attention back to the present.

Learn from Others

Observe how others around you cope with uncertainty. Talk to them about their experiences and see if you can adopt some of their strategies.

You can also learn from therapists and self-help resources that provide evidence-based strategies for managing intolerance of uncertainty.

References

Akbari, M., Sheikhi, S., Navab Safiadin, M. S., Rahmani, M., Forootan, R., & Asmundson, G. J. G. (2026). A hierarchical uncertainty framework of anxiety: Preregistered meta-analytic structural model of intolerance of uncertainty and worry across anxiety disorders. Clinical Psychology Review, 128, 102773. https://doi.org/10.1016/j.cpr.2026.102773

Bird, S., Moid, L. A. E., Jones, C. A., & Surtees, A. D. (2024). The relationships between restrictive/repetitive behaviours, intolerance of uncertainty, and anxiety in autism: A systematic review and meta-analysis. Research in Autism Spectrum Disorders, 117, 102428. https://doi.org/10.1016/j.rasd.2024.102428

Carleton, R. N., Collimore, K. C., & Asmundson, G. J. (2010). “It’s not just the judgements—It’s that I don’t know”: Intolerance of uncertainty as a predictor of social anxiety. Journal of Anxiety Disorders, 24(2), 189-195. https://doi.org/10.1016/j.janxdis.2009.10.007

Carleton, R. N., Sharpe, D., & Asmundson, G. J. (2007). Anxiety sensitivity and intolerance of uncertainty: Requisites of the fundamental fears?. Behaviour research and therapy, 45(10), 2307-2316. https://doi.org/10.1016/j.brat.2007.04.006

Carleton, R. N. (2016). Fear of the unknown: One fear to rule them all? Journal of Anxiety Disorders, 41, 5-21. https://doi.org/10.1016/j.janxdis.2016.03.011

Dugas, M. J., Gagnon, F., Ladouceur, R., & Freeston, M. H. (1998). Generalized anxiety disorder: A preliminary test of a conceptual model. Behaviour Research and Therapy, 36(2), 215-226. https://doi.org/10.1016/S0005-7967(97)00070-3

Dugas, M. J., Ladouceur, R., Léger, E., Freeston, M. H., Langlois, F., Provencher, M. D., & Boisvert, J.-M. (2003). Group cognitive-behavioral therapy for generalized anxiety disorder: Treatment outcome and long-term follow-up. Journal of Consulting and Clinical Psychology, 71(4), 821-825. https://doi.org/10.1037/0022-006X.71.4.821

Jenkinson, R., Milne, E., & Thompson, A. (2020). The relationship between intolerance of uncertainty and anxiety in autism: A systematic literature review and meta-analysis. Autism, 24(8), 1933-1944. https://doi.org/10.1177/1362361320932437

Jacoby, R. J. (2020). Intolerance of uncertainty. In J. S. Abramowitz & S. M. Blakey (Eds.), Clinical handbook of fear and anxiety: Maintenance processes and treatment mechanisms (pp. 45–63). American Psychological Association. https://doi.org/10.1037/0000150-003

McEvoy, P. M., Hyett, M. P., Shihata, S., Price, J. E., & Strachan, L. (2019). The impact of methodological and measurement factors on transdiagnostic associations with intolerance of uncertainty: A meta-analysis. Clinical Psychology Review, 73, 101778. https://doi.org/10.1016/j.cpr.2019.101778

Morriss, J., & Ellett, L. Intolerance of uncertainty, paranoia, and prodromal symptoms: Comparisons between a schizophrenia spectrum disorder, anxiety disorder and non-clinical sample. Psychology and Psychotherapy: Theory, Research and Practice. https://doi.org/10.1111/papt.12599

Pinciotti, C. M., Riemann, B. C., & Abramowitz, J. S. (2021). Intolerance of uncertainty and obsessive-compulsive disorder dimensions. Journal of Anxiety Disorders, 81, 102417. https://doi.org/10.1016/j.janxdis.2021.102417

Ren, L., Wei, Z., Li, Y., Cui, L. B., Wang, Y., Wu, L., … & Liu, X. (2021). The relations between different components of intolerance of uncertainty and symptoms of generalized anxiety disorder: a network analysis. BMC psychiatry, 21, 1-11. https://doi.org/10.1186/s12888-021-03455-0

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