How do time estimation errors occur in autism? 

Time estimation errors are common in autism and stem from well-documented differences in executive functioning, temporal processing and attention. NHS, NICE and peer-reviewed research (2022) all recognise that autistic people may experience challenges estimating how long tasks will take, tracking the passage of time and managing time-dependent routines. These difficulties are cognitive in nature, not motivational, and often require specific kinds of support. 

Why autistic people may misjudge time 

NHS-aligned resources explain that autistic people frequently experience differences in planning, sequencing, working memory and attention shifting, all of which shape how time is perceived. Services such as Leicestershire NHS and Nottinghamshire Healthcare describe how these skills influence the ability to judge how long tasks will take, remember steps, and process information quickly enough to stay on schedule. When these executive processes work differently, everyday timing errors can appear, arriving late, underestimating or overestimating duration, or struggling to complete tasks within set timeframes. 

What NICE says about time-related difficulties 

NICE guidelines for adults (CG142) and children and young people (CG170) confirm that autistic people commonly experience difficulties with planning, organisation, sequencing and time management. These challenges can affect daily-living skills, schoolwork, employment, attending appointments and managing transitions. NICE recommends reasonable adjustments such as visual schedules, structured routines, visual timers and breaking tasks into simpler steps to help reduce timing errors. 

Why time estimation errors happen 

Research shows that autistic people may experience differences in temporal processing, time-based prospective memory, and duration estimation. Studies such as those published in the Journal of Autism and Developmental Disorders report that autistic individuals may under- or overestimate time, especially when cognitive load is high or when tasks require attention shifting.  Mechanisms that contribute to these errors include: 

• Slower processing speed, making tasks feel longer or harder to judge 

• Working-memory limitations, reducing the ability to track multiple time-dependent steps 

• Monotropism, where deep focus on one activity reduces awareness of time passing 

• Weak central coherence, making it harder to integrate steps into a whole sequence 

• Higher cognitive load, which reduces timing accuracy 

These cognitive patterns help explain everyday experiences such as losing track of time, misjudging how long tasks will take or finding transitions unexpectedly difficult. 

Real-world impact 

NHS and NHS England highlight practical consequences of time-estimation differences, including missed appointments, difficulties with schoolwork, challenges managing work deadlines and problems with daily routines (NHS England guidance). Autistic people may also experience stress or overwhelm when timing expectations don’t match internal perception. 

Strategies that make time clearer 

NHS, NICE and the National Autistic Society recommend several approaches: 

• Visual timers and countdown clocks 

• Visual schedules that show tasks in order 

• Breaking tasks into smaller, timed steps 

• Predictable routines with advance notice for changes 

• Calendars, apps and reminders to support time-dependent tasks 

According to NICE, structured routines and visual supports can meaningfully reduce timing errors and improve day-to-day functioning.  

The takeaway 

Time estimation errors in autism are grounded in differences in executive functioning and temporal processing, not a lack of effort or awareness. With structured routines, visual tools and supportive adjustments, many autistic people can navigate time more confidently and reduce stress around daily demands.