NPL provides top-level reference standards for time and is the UK's centre for precise time measurement.

The activities of NPL's time group explained - including the operation of the atomic clocks that form the national time scale and the broadcast of the MSF time signal that is used to set radio-controlled clocks throughout the UK. NPL has also provided enhanced time scale algorithms for Galileo -; the European satellite navigation system - by combining the signals from multiple atomic clocks into a highly accurate 'ensemble'.