The simple answer is no!
It's a common belief that electrical appliances within the workplace need to be PAT tested on an annual basis, but this isn't true. The Electricity at Work Regulations (1989) state that any electrical equipment with the potential to cause harm should be maintained and kept in a safe condition. The regulations do not specify exactly what needs to be done or who should do it, and they also don't say how frequently equipment should be maintained - this means that they don't make inspection or testing of electrical appliances a legal requirement.
However, this doesn't mean that you should never test your electrical appliances; it just means that not every electrical appliance will require the same frequency or level of testing. For example, if you work on a construction site, your portable tools should be tested / inspected on a regular basis, whereas a printer in an office environment isn't likely to become damaged so will not require testing as often.
Another thing you may be wondering is who should carry out the checks / tests? The common belief is that a qualified electrician must do this on your behalf; but again, this isn't true. In low risk environments, a competent member of staff can easily undertake any visual inspections (assuming that they have enough knowledge and training). A greater level of knowledge will usually be required when undertaking combined inspection and testing. Things like necessary equipment, knowledge of the equipment and the ability to understand test results all need to be considered.
If you would like more information on how to maintain electrical equipment, the HSE provide some useful downloadable documents on the issue, one for generic use (e.g. people working on construction sites) and another for low risk environments (e.g. offices).