Smart meters in the UK are presented as a simple upgrade: no estimated bills, real-time energy usage data, and easier switching. What is rarely explained clearly is that installing a smart meter involves agreeing to the collection and use of detailed energy consumption data — information that can reveal when you're home, what appliances you use, and patterns in your daily life. The smart meter rollout is governed by the Smart Energy Code, Ofgem's licence conditions, and the UK GDPR. These frameworks provide real protections, but only if you understand them. The terms of your energy supply contract — and what you agree to when the installation team visits — determine how your data is used and what you can do about it.
What is a Smart Meter Agreement?
A smart meter is a digital gas or electricity meter that sends consumption readings directly to your energy supplier. Installation is voluntary — you cannot be forced to have one installed. Once installed, smart meters communicate via the Data Communications Company (DCC), a government-licensed intermediary. Your energy supplier receives half-hourly consumption data by default. You can opt down to daily or monthly readings under the Smart Meter Installation Code of Practice (SMICoP) — but only if you know to ask. The data collected is personal data under UK GDPR and is subject to your energy supplier's privacy notice.
Red flags to watch for
Half-hourly data creates a granular picture of your household activity. You have the right under SMICoP to request daily or monthly readings instead, but suppliers must make this clear. If they don't mention it, ask explicitly.
Some energy suppliers' terms permit sharing smart meter data with affiliated companies for marketing purposes. Under UK GDPR, you should be able to opt out of this use.
You have the right to have a smart meter installed in 'dumb mode' — communicating at the minimum data frequency — without losing the ability to upgrade later. Contracts should acknowledge this.
UK GDPR requires that personal data is kept no longer than necessary. Your energy contract's privacy notice should specify how long consumption data is retained and what happens to it after you switch supplier.
If your contract doesn't require consent before switching you to a time-of-use tariff based on smart meter data, your bills could change without a meaningful choice.
Your legal rights
Smart meter data is personal data under the UK GDPR and Data Protection Act 2018. You have rights to access, correct, and delete your data, and to object to processing for direct marketing. Under Ofgem's licence conditions and the Smart Meter Installation Code of Practice (SMICoP), installation must be offered — not mandated. The Smart Energy Code (SEC) governs data access by your supplier, network operator, and authorised third parties. You can request a copy of all data collected about you via a Subject Access Request (SAR) to your supplier, free of charge. Ofgem is the regulator for energy suppliers and can be contacted at ofgem.gov.uk.
Questions to ask before you sign
- 1Will my smart meter transmit half-hourly data by default, and how do I opt down to daily or monthly readings?
- 2Who will have access to my consumption data — just you, your group companies, or third parties?
- 3Can I opt out of marketing based on my smart meter data?
- 4What happens to my data if I switch energy supplier?
- 5How long do you retain my smart meter consumption data?
- 6Can the smart meter be operated in 'dumb mode' and can I upgrade to full smart functionality later?
Disclaimer: This guide is for educational purposes only and does not constitute legal advice. Contract law varies by jurisdiction and individual circumstances. Always consult a qualified legal professional before making decisions based on this information.