German Time Act

[German original]


German Federal Law Journal (Bundesgesetzblatt, BGBl.), 1978, Part I, pp. 1110–1111

Act on the definition of time (Zeitgesetz — ZeitG)

25 July 1978

last amended by act on 13 September 1994 (BGBl., Teil I, p. 2322)

The [Lower House of the German] Federal Parliament has passed the following act:

§ 1 Legal time

(1) In official and business communication, date and time are used according to legal time.

(2) Legal time is Central European Time. It is defined as Coordinated Universal Time plus one hour.

(3) Coordinated Universal Time is defined as a time scale with the following properties:

  1. On 1 January 1972, 0 hours, it corresponds to 31 December 1971, 23 hours, 59 minutes, 59.96 seconds mean solar time on the null meridian.
  2. The scale unit is the base unit second according to section 3 paragraph 4 of the act on units of measurement of 2 July 1969 (BGBl. I, p. 709), last amended by article 287 number 48 of the act of 2 March 1974 (BGBl. I, p. 469), at sea level.
  3. The time scale Coordinated Universal Time is kept in alignment with mean solar time at the null meridian with a tolerance of not more than one second, either by inserting one additional second or by omitting one second.

(4) While in force, Central European Summer Time is legal time. Central European Summer Time is defined as Coordinated Universal Time plus two hours.

§ 2 Representation and dissemination of legal time

Legal time is represented and disseminated by the [German] Federal Physics and Technology Agency [Physikalisch-Technische Bundesanstalt, PTB].

§ 3 Authorization for introducing Central European Summer Time

(1) The [German] federal government is authorized, for better utilization of day light and for alignment of time keeping with neighbour countries, to introduce Central European Summer Time by decree for a time interval between 1 March and 31 October.

(2) Central European Summer Time shall start and end on a Sunday, respectively. The federal government determines in the decree according to paragraph 1 the day and the time of day at which Central European Summer Time starts and ends, as well as the designation of the hour that appears twice at the end of Central European Summer Time.

§ 4 Other regulations

§ 9a of the aviation regulation, as well as time regulations that result from the implementation of international treaties, remain unaffected.

§ 5 Coming into force; replacement of other regulations

This act shall take effect from the day following its proclamation. At the same time, the act regarding the introduction of a uniform time definition, published in BGBl. III, division number 7141-1, in revised form, goes out of force.


Translation by Markus Kuhn

On 12 July 2008, the above Time Act was replaced by the Act on Units of Measurement and Definition of Time (BGBl. I S. 1185). The new definition of legal time there now only refers to “Coordinated Universal Time”, without detailing its definition or leap seconds any further.

created 2003-07-30 – last modified 2013-06-19 – http://www.cl.cam.ac.uk/~mgk25/time/zeitgesetz.en.html