This blogpost, republished from FFT Education Datalab, reports findings from Nuffield Foundation-funded research conducted into teacher health and wellbeing.

Much has been written about the working hours of teachers over the last five years, and it is something we have blogged about previously as well.

One of the reasons why this has become such a hot topic among teachers, school leaders and education policymakers is that working hours are thought to be linked to teacher wellbeing. That is, the more teachers work, the more stressed they become. This, in turn, potentially impacts upon their mental health.

Yet there has actually been precious little attempt to quantify this relationship. How strong is the link between working hours and teacher wellbeing? And does it matter how those working hours are comprised?

This blogpost – drawing upon evidence from a new paper I have just published with colleagues, using TALIS 2018 data from five English-speaking countries – starts to fill that gap. (TALIS is the OECD’s Teaching and Learning International Survey.)

Longer working hours, lower wellbeing

TALIS 2018 collected information from teachers on their working hours and time spent upon different tasks, while also asking a series of questions about the impact that their job has on their wellbeing (e.g. the extent that teachers agree with statements such as ‘I experience stress in my work’ and ‘my job negatively impacts my mental health’).

The table below provides results illustrating how teachers’ total working hours and responses to these ‘workplace wellbeing’ questions (transformed into a continuous scale) are related. Results are reported in terms of an ‘effect size’ – a measure of the strength of the association between an explanatory factor (e.g. working hours) and an outcome (e.g. wellbeing).

In all countries, longer working hours are associated with a decline in teacher wellbeing. Specifically, a 10-hour increase in a teacher’s working week is associated with between a 0.1 and 0.2 effect size decline in wellbeing (a negative, though relatively modest, effect). However, as we discuss in our paper, the figures may well be underestimates (due to measurement error), with the real effect being even bigger.

Of course, the relationship between teachers’ working hours and their wellbeing may not be linear.

For instance, if you only work 35-hours a week, then adding in an extra hour or two may not have serious consequences. On the other hand, if you are already working 60-hours plus per week (as around a quarter of full-time teachers in England say they do during term-time at least), then an additional hour of work could be the straw that breaks the camel’s back.

Total working hours and wellbeing

The chart below investigates this issue, exploring the association between each additional hour that teachers work and their wellbeing. Note that, in this graph, what we are most interested in is the shape of the curves plotted, rather than their absolute levels. Positive effect sizes correspond to a decrease in wellbeing.

The association between total working hours and workplace wellbeing

Notes: Results shown for teachers working between 40 and 65 hours per week (approximately the 10thand 90th percentile of the working hours distribution).

Focusing upon the results for England, for secondary teachers the association between working hours and wellbeing is roughly linear. That is, it does not matter if you are working 40 hours, 50 hours or 60 hours each week, each extra hour of work seems to have broadly the same (negative) effect upon workplace wellbeing. This pattern is observed in most of the countries we considered.

Interestingly, one exception seems to be primary teachers in England. For this group the curve is pretty flat between 40 and 55 hours per week. In other words, adding in an additional hour of work for teachers in this range may do little to affect their wellbeing. On the other hand, once primary teachers in England exceed 55 hours per week, each extra hour worked leads to a sizeable decline in their wellbeing.

Why the difference between primary and secondary teachers? The honest answer is I have no idea – and do not wish to speculate.

What the chart does helpfully demonstrate, though, is that we should not assume that reducing working hours will have the same potential benefits on wellbeing for everyone. It may well be that, in some settings, it is those working the longest hours that would benefit the most.

Considering type of work

Of course, not all types of work are equal. Teachers may not mind an additional hour of contact with the pupils that they teach; it is the extra hour of marking that they may dread.

The chart below probes this particular issue. It illustrates how an extra hour per week spent upon six different types of task are linked to teacher wellbeing. Note again that positive effect sizes mean a decrease in wellbeing.

What does this tell us?

Well, rather than being detrimental, extra time spent upon team working and professional development may have some benefits for teacher wellbeing. Surprisingly, the association between time spent upon management/administration and teacher wellbeing is also relatively weak.

The two things that really seem to matter, though, are marking and lesson preparation. Each extra hour teachers spend doing these tasks is particularly strongly associated with declines in their wellbeing.[1]These are, of course, tasks that often take place in the evening, at weekends and during school holidays – invading teachers’ personal time and affecting their work-life balance.


These findings are of course all correlational, rather than causal, and so we do need to be a little bit careful when interpreting the results.

They do, nevertheless, offer some pointers for education policy – including the areas that government and school leaders may want to focus upon to improve the wellbeing of teaching staff.

The project has been funded by the Nuffield Foundation, but the views expressed are those of the authors and not necessarily the Foundation. Visit

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  1. While in absolute terms the effect sizes are small, we’re talking about the effect caused by a very small change in working hours – an increase of only an hour per week.