Guidance

Annex B: communications data code of practice (accessible)

Updated 6 June 2025

This flow chart, and the definitions therein, have been simplified for ease of reference. If, in making a determination, you are testing the meaning of individual words, please refer to the original text in the Act or obtain legal advice.

Tab 1: entity or events data

To note: Entity CD which can only be derived from ICRs will be an exception to the flow shown in the diagram because 62((5)(a)(ii) has the effect of raising the threshold to 鈥榮erious crime鈥�.

Question 1

Is the data about:

  1. a person or thing OR
  2. an association between a person or thing and a telecommunication service OR
  3. an association between a person or thing and a telecommunications system? (see below)

Yes

Go to question 2.

No

Your data is not entity data, or events data or Communications Data (CD).

Question 2

And does it include data which identifies or describes that person or thing?

Yes

Go to question 3.

No

Your data is not entity data, or events data or Communications Data (CD).

Question 3

And does the data include events data - that is data:

  1. about an event that occurred on, in or by means of a telecommunications system; and
  2. consisting of one or more persons or things engaging in a specific activity at a specific time.

Yes

Your data is events data. Move to Crime Tab.

No

Your data is entity data. Move to Crime Tab.

Definitions

Telecommunications Operator

Means a person who provides a telecommunications service to persons in the UK or controls a telecommunication system which is either in the UK, or is outside the UK but is used by another person to provide a telecommunications service to persons in the UK.

Telecommunications Service

Means any service that provides access to, and use of, any telecommunication system, and includes a service which enables the creation, management or storage of communications transmitted by such a system.

Telecommunication System

Means a system that exists for the purpose of enabling the transmission of electronic communications

Communication

In relation to a telecommunications operator, service or system, includes anything comprising speech, music, sounds, visual images or data of any description, and associated signals used to transmit anything between persons and/or things.

Tab 2: crime or serious crime

There are 6 other lawful purposes for disclosure of CD in addition to applicable crime purpose:

  1. in the interests of national security,
  2. in the interests of the economic well-being of the UK so far as those interests are also relevant to the interests of national security,
  3. in the interests of public safety,
  4. for the purpose of preventing death or injury or any damage to a person鈥檚 physical or mental health, or of mitigating any injury or damage to a person鈥檚 physical or mental health,
  5. to assist investigations into alleged miscarriages of justice, or
  6. where a person (鈥淧鈥�) has died or is unable to identify themselves because of a physical or mental condition鈥�
    • (i)to assist in identifying P, or
    • (ii)to obtain information about P鈥檚 next of kin or other persons connected with P or about the reasons for P鈥檚 death or condition.

For more information please refer to the .

From tab 1 - entity data - start here

Is the purpose of the disclosure:

  1. the prevention or detection of crime, that is the investigation of conduct which constitutes one or more criminal offences OR

  2. is for the purpose of preventing disorder? 鈥淒etecting crime鈥� includes establishing the circumstances in which a crime was committed and the apprehension of the person by whom the crime was committed.

Yes

Crime threshold is met for the disclosure of entity data - move to CD tab

No

Crime threshold is not met for the disclosure of entity data. Consider other statutory purposes for which CD can be acquired or other information gathering powers available to you. e.g. is the purpose of your investigation other than in support of a criminal prosecution - is it civil in nature? Are your general information powers exercised in connection with either the regulation of persons or activities or the checking, monitoring or enforcement of compliance with requirements, prohibitions or standards imposed by law.

From Tab 1 - events data - start here

Is the purpose of the disclosure the prevention or detection of serious crime? Serious crime means:

  1. a crime where the offence is one for which a person who has reached the age of 18 (or, in relation to Scotland or Northern Ireland, 21) and has no previous convictions, is capable of being sentenced to imprisonment for a term of 12 months or more OR

  2. the crime:

    • i) involves the use of violence, or
    • ii) results in substantial financial gain, or
    • iii) is conduct by a large number of persons in pursuit of a common purpose, or
    • iv) is an offence by a person who is not an individual (for example a corporate or unincorporated company or business), or
    • v) which involves, as an integral part of it, the sending of a communication or a breach of a person鈥檚 privacy.

Yes

Serious crime threshold IS met for the disclosure of Events data - Move to CD tab

No

Serious crime threshold IS NOT met for the disclosure of events data. Consider other statutory purposes for which CD can be acquired or other information gathering powers available to you. e.g., is the purpose of your investigation other than in support of a criminal prosecution - is it civil in nature? Are your general information powers exercised in connection with either the regulation of persons or activities or the checking, monitoring or enforcement of compliance with requirements, prohibitions or standards imposed by law.

Tab 3: comms data Y or N

CD, in relation to a telecommunications operator, telecommunications service or telecommunication system, means entity data or events data 鈥� (s261(5)).

261(5)(a)

Is or can the data be obtained by a telecommunications operator?

AND

Is the data about a person or thing to which a telecommunications service is provided AND relates to the provision of that service?

OR

Is the data in, part of, attached to or otherwise logically associated with a communication for the purposes of the telecommunications system by which the communication will be transmitted?

OR

Does the data relate to the use of a telecommunication service or system?

AND

Does NOT include any content of a communication, that is any element of the communication which reveals anything of what might reasonably be considered to be the meaning of the communication, but any meaning arising from the fact of, or relating to the transmission of, the communication or is to be disregarded. Content also excludes 鈥榬elevant subscriber data鈥� which is data - other than data comprised in a recording of speech, which is about an entity to which a telecommunication service is provided and constitutes any of the content of a communication made for the purpose of initiating or maintaining an entity鈥檚 access to a telecommunication service. e.g. subscriber data passed in an online form. Data which is systems data is not content. 鈥淪ystems data鈥� is data that enables or facilitates, or identifies or describes anything connected with enabling or facilitating, the functioning of a telecommunication system or service. [The definition of systems data is broader than this, but these are the most relevant elements of that definition. It is recommended to seek legal advice if this definition is important to your acquisition of CD.]

Yes

Your data meets the definition of CD.

261(5)(b)

Is the data available directly from a telecommunications system and is the data in, part of, attached to or otherwise logically associated with a communication for the purposes of the telecommunications system by which the communication will be transmitted?

Does NOT include any content of a communication, that is any element of the communication which reveals anything of what might reasonably be considered to be the meaning of the communication, but any meaning arising from the fact of, or relating to the transmission of, the communication or is to be disregarded. Content also excludes 鈥榬elevant subscriber data鈥� which is data - other than data comprised in a recording of speech, which is about an entity to which a telecommunication service is provided and constitutes any of the content of a communication made for the purpose of initiating or maintaining an entity鈥檚 access to a telecommunication service. e.g. subscriber data passed in an online form. Data which is systems data is not content. 鈥淪ystems data鈥� is data that enables or facilitates, or identifies or describes anything connected with enabling or facilitating, the functioning of a telecommunication system or service. [The definition of systems data is broader than this, but these are the most relevant elements of that definition. It is recommended to seek legal advice if this definition is important to your acquisition of CD.]

Yes

Your data meets the definition of CD.

261(5)(c)

Is or can the data be obtained by a telecommunications operator?

AND

Is the data about the architecture of a telecommunication system?

AND

Is not about a specific person?

AND

Does NOT include any content of a communication, that is any element of the communication which reveals anything of what might reasonably be considered to be the meaning of the communication, but any meaning arising from the fact of, or relating to the transmission of, the communication or is to be disregarded. Content also excludes 鈥榬elevant subscriber data鈥� which is data - other than data comprised in a recording of speech, which is about an entity to which a telecommunication service is provided and constitutes any of the content of a communication made for the purpose of initiating or maintaining an entity鈥檚 access to a telecommunication service. e.g. subscriber data passed in an online form. Data which is systems data is not content. 鈥淪ystems data鈥� is data that enables or facilitates, or identifies or describes anything connected with enabling or facilitating, the functioning of a telecommunication system or service. [The definition of systems data is broader than this, but these are the most relevant elements of that definition. It is recommended to seek legal advice if this definition is important to your acquisition of CD.]

Yes

Your data meets the definition of CD.