There are strict rules under the Working Time Regulations about your right to rest breaks at work. If your employer is breaching these rules, then their actions will not be legal.
The law says that most workers who work for more than six hours per day the right to take a break of at least 20 minutes. Young workers aged 16 and 17 have the right to a 30-minute break if they work more than four and half hours per day.
These rest breaks must be taken during the six-hour period, not at the beginning or end of it. The exact timing of the breaks can be decided by the employer. Your employer also needs to make sure that working arrangements are such that you can take your rest break. These breaks may be unpaid. However, remember that these entitlements are the minimum that the law allows. You may have better rights through your contract of employment, so make sure you understand the policy in your own workplace. In unionised workplaces, unions have often negotiated for the break to be paid rather than unpaid.
There are some circumstances that allow employers to reschedule these breaks, as long as they give 'compensatory rest' – i.e. the same length of break later in the working day. This leeway could be applied on a regular basis to a wide range of industries that require a continuous service. These include security, hospitals, residential homes, prisons, docks, airports, press, radio, cinema, telecoms, police, fire, ambulance, coastguard, gas, water, electricity, refuse collection and disposal, research and development, and agriculture.
Your breaks can also be delayed in any industry where "there is a foreseeable surge in activity". A 'foreseeable surge' should involve an exceptional level of activity. In reality, your employer should employ extra staff over the Christmas period, rather than expecting existing staff to delay their rest break. However, your employer does have to substitute the same length of break time within the same six hours or more.
‘Compensatory rest’ simply means that your rest break is rescheduled to later in the day. It must still be a genuine break from work and must, as far as possible, be free from work for at least 20 minutes. It can’t, for example, be made up of several shorter chunks of time that together make up 20 minutes.