Data Sharing under UK GDPR: Key Considerations for Internal and External Sharing

For all organisations the ability to share personal data effectively and responsibly is crucial. Whether that’s sharing data internally or with external partners and service providers, organisations must navigate a complex web of legal obligations. Under the UK General Data Protection Regulation (UK GDPR), any such sharing of personal data must be carried out lawfully, fairly and transparently. This blog explores the key considerations and implications of sharing personal data both internally and externally under the UK GDPR.

For those navigating complex data sharing scenarios, expert advice is available – contact us today to discuss how we can help.

Internal Data Sharing under UK GDPR: What to Know

Internal data sharing refers to the transfer or access of personal data between different parts of the same organisation. While the data may never leave the business as such, it’s still subject to UK GDPR. Organisations must ensure that internal data flows are lawful, purposeful and proportionate. Common examples of internal data sharing include:

• HR sharing employee data with payroll or IT teams
• Customer support sharing customer/user information with product/technical teams
• Sales and marketing teams sharing contact data relating to potential or existing customers

To learn more about how your organisation can meet its data protection obligations with confidence, visit our Data Protection Services page.

External Data Sharing & Third Parties: GDPR Rules

External data sharing involves disclosing personal data to third parties such as service providers, partners, regulators or other organisations. Importantly, these individuals or organisations are outside your own organisational structure. Under UK GDPR, this sharing triggers heightened legal responsibilities and requires careful management of risk. Examples of external data sharing include:

• Sharing data with cloud service providers (processors)
• Partnering with marketing agencies
• Using an external payroll system

Key UK GDPR Considerations:

External data sharing must be lawful, transparent and secure, regardless of who the recipient is. Key factors include: 

1. Data Controllers vs. Data Processors
   When sharing data externally, the first step is to determine the roles, i.e. is this a Data Controller to Data Processor relationship, and which organisation is which? Controllers determine the purpose and means of processing; processors act on behalf of the controller.
2. Data Processing & Data Sharing Agreements
   If you’re sharing data with a processor, a written contract (often in the form of a separate Data Processing Agreement) is mandatory and must include specific clauses outlined in Article 28. For controller-to-controller sharing, a data sharing agreement is highly recommended, though not legally required.
3. Transparency and Individual Rights
   Data subjects must be informed about how and with whom their data is shared, typically via privacy notices. Failure to do so may breach the transparency principle of the UK GDPR.
4. International Transfers
   If data is shared outside the UK (to a “third country”), appropriate safeguards must be in place, such as Standard Contractual Clauses (SCCs) or adequacy decisions. This may result in additional contractual documentation being required.
5. Security and Risk Management
   External sharing must be accompanied by appropriate security measures. Due diligence on third parties is essential to ensure their compliance with UK GDPR standards.

Potential Consequences of Non-Compliance

Failure to manage data sharing in line with the UK GDPR exposes organisations to serious consequences – both legally and operationally. Even well-intentioned data disclosures, if handled improperly, can result in regulatory action and lasting reputational damage:

• Financial Penalties: Fines of up to £17.5 million or 4% of annual global turnover, whichever is higher
• Reputational Damage: Loss of customer trust and media scrutiny
• Legal Action: Data subjects may seek compensation for breaches of their rights
• Operational Disruption: Regulatory investigations can impact business continuity

Best Practices for GDPR-Compliant Sharing

To ensure data sharing – whether internal or external – meets the requirements of UK GDPR, organisations must take a proactive approach to privacy governance. Here are a few best practices to minimise risk and demonstrate accountability:

• Map your data flows to understand where personal data moves within and outside your organisation. This means putting together, and keeping up to date, a Record of Processing Activities (ROPA).
• Conduct DPIAs when necessary, especially for new or high-risk sharing.
• Maintain up-to-date privacy notices to ensure individuals are informed.
• Train staff on data protection practices, internal processes and secure data handling.