What does data minimisation mean?
Data minimisation is one of the seven core data protection principles outlined by the UK GDPR. Its definition reads: “personal data shall be adequate, relevant and limited to what is necessary in relation to the purposes for which they are processed”.
The practical implementation of this principle requires applying two concepts to the processing of personal data: necessity and proportionality. While applying data minimisation can be straightforward in some scenarios, it can pose a significant challenge in others.
This guide will help you understand the principle of data minimisation, what it requires, and the practical steps you can take to ensure compliance.
Necessity, proportionality and storage limitation
Your organisation, when acting as a controller, must assess whether the personal data they collect (or intend to) is suitable and reasonable to accomplish their specific purposes. Personal data is considered suitable if its very nature is fundamentally necessary to achieve the stated purpose. Meanwhile, personal data is considered adequate, meaning complete and sufficient to properly fulfil your stated purpose, if both the nature and the total volume of that data are proportionate to the objective.
Personal data fields are only considered necessary if the defined purpose cannot be achieved without them. If the objective, can be successfully fulfilled by collecting fewer data fields, the additional ones are unnecessary and must be excluded.
Example – if you are organising an online event, you only need the potential participants’ name and email address to provide them with access details to the event. You do not strictly need to know their gender, home address or health information. You should avoid asking for these details and limit collection and processing to what is required for that specific event.
In terms of proportionality, your organisation should also consider the amount of data to be collected and its adequacy in relation to the purpose. Gathering large amounts of data without any restrictions will be considered excessive. A “save-everything” or “just-in-case” approach to data collection is inherently disproportionate and constitutes a direct breach of the data minimisation principle.
Example – a gym develops a mobile app for members to book workout classes. When setting up an account, as a requirement to book the classes the app asks members to input their height, weight, and any chronic medical conditions to provide progress towards users’ health goals. This type of tracking is not proportionate for the original purposes as collection of data fields is quite extensive. A simple, proportionate alternative is to only require a name and membership number to book a class.
Before processing personal data, your organisation must carefully evaluate how it might negatively impact people’s privacy. As part of this assessment, it is important to check if there are alternative, less invasive ways to achieve the same objective. If a different method exists your organisation must choose the alternative that carries less risks.
Your organisation must only store data for as long as it is needed to fulfil its intended purpose. This means establishing clear retention schedules and secure deletion protocols to ensure that obsolete files are permanently destroyed. Additionally, you must conduct regular reviews to prevent inaccuracies, maintain data integrity, and ensure all remaining information stays up to date.
The commercial, legal and operational risks of non-compliance
When processing of data is excessive or inadequate and is not in line with the criteria explained above, this could result in a series of commercial, legal and operational risks that can affect your organisation.
- Regulatory fines and legal claims
The Information Commission (formerly ICO), in accordance with Article 83 of the UK GDPR, can enforce strict penalties for infringements of the core principles of processing including data minimisation. Specifically, the penalties can go up to £17.5 million or up to 4% of the total worldwide annual turnover of the preceding financial year, whichever is higher. - Vulnerability and data breach exposure
Excessive data retention can increase exposure to data breaches and unauthorised or unlawful access to data and make your organisation a more appealing target for malicious actors, creating additional vulnerabilities that must be actively secured and monitored. Ultimately, this can convert a minor security incident into a much larger and more costly compliance failure. - Increased storage and operational costs
Collecting extensive amounts of data can inflate cloud infrastructure and server hosting fees. Additionally, it can increase the cost of data management tools such as security monitoring software, and system backups. - Additional difficulties in complying with data access requests
Under the UK GDPR, individuals have a right to access their data via Subject Access Requests (SARs). If your organisation holds an unorganised, broad storage of personal information, fulfilling a SAR would require going through more data to locate the relevant files and redact third-party details potentially interfering with statutory deadlines. - Erosion of trusts and credibility
When your organisation collects or retains more data than is demonstrably necessary, it signals a lack of data governance and compliance with privacy frameworks. Should these excessive data collection practices be exposed, through a regulatory investigation, media coverage, or a data breach incident, the resulting reputational damage can be severe. - Data inaccuracy and workflow inefficiency
If your organisation stores files indefinitely without a structured disposal policy, its databases could become congested with obsolete, redundant, and inaccurate records. This accumulation of outdated data can compromise operational efficiency. - Workforce liability
A lack of staff awareness regarding data management policies introduces significant operational and compliance vulnerabilities. Employees might collect excessive personal information under the assumption that more data is always beneficial.
Building data minimisation into your organisation
By embedding data protection into operational workflows, an organisation can systematically mitigate compliance risks, lower operational overhead, and strengthen consumer trust. The following structured approach outlines the foundational steps required to operationalise data minimisation, transitioning from initial assessment to continuous internal governance.
- Conduct a comprehensive initial data audit
Carrying out a general data audit involves mapping out exactly what personal data is currently being collected, where it is stored, who has access to it, and how the data flows are structured. This assessment can allow your organisation to identify areas of over-collection and structural vulnerability. - Define necessity, proportionality and purpose
As outlined above, your organisation must evaluate the purpose of every data processing activity and determine if it is genuinely necessary and proportionate to achieve that objective. This is required to comply with the UK GDPR and additionally it helps increasing consumer trust and avoid potential regulatory fines. - Identify any potential risk or vulnerability
Operationalising data minimisation requires a proactive risk assessment. Your organisation must identify where their current data processing activities and overall data management framework can create liabilities and risks as outlined above. Identifying these areas allows mitigation and prevention measures to be put in place. - Design policies and procedures
Drafting clear, enforceable policies and standard operating procedures that explain how data should be handled in order to achieve full compliance with the principle of minimisation as well as the other core data protection principles. Policies and procedures serve as guideline for daily operations. For instance, you should consider drafting clear data retention schedules, a secure disposal and destruction policy, as well as a Record of Processing Activities (ROPA). - Establish retention and deletion schedules
Organisations must establish clear data retention schedules that define explicit lifecycles for different categories of information and provide review schedules to ensure storage of data remains compliant. Once a retention period expires, automated or manual procedures must provide the permanent, secure deletion or anonymisation of that data, eliminating unnecessary and excessive storage of data, preventing the consequent financial burden as well as minimising potential data breach risks. - Perform routine compliance audits
Compliance is not a one-off exercise, instead it is a continuous process that needs to be embedded in your organisation workflow. Establishing routine, scheduled audits ensures that data minimisation practices remain effective as the organisation extends or modifies its processing activities and data management structures.
Conclusion
Data minimisation is not merely a passive regulatory requirement, it is a foundational pillar of data governance.
By establishing and following a structured approach your organisation can successfully align with the mandate of the UK GDPR while simultaneously avoiding regulatory fines, lowering the financial burden of data storage, and ensuring that data assets remain accurate and secure.
Your organisation does not need to develop this framework alone, at IGS we can help you ensure full compliance by helping you build data minimisation into your daily operations.
If you would like help reviewing your data protection obligations, understanding where your organisation’s risk lies, or upskilling your team through practical training, please contact us at info@informationgovernanceservices.com or 0208 106 7936.
