The ICO exists to empower you through information.

Do I need to report a breach?

If you are unsure whether your organisation needs to report a breach to the ICO, use our self-assessment tool or read our examples.  


We have a simple guide to help small companies and sole traders in the first 72 hours after discovering a breach.

We also have a detailed guide about how to manage a breach, including risk assessments and informing individuals.

How do I report a breach?

You can report a breach online. The online form should take approximately 30 minutes to complete. Please ensure you have all the details regarding the breach ready before you start – you can't save the form and return at a later date.

Start now


Fersiwn beta o'r ffurflen we ar gyfer rhoi gwybod am dor data personol sydd ar gael ar hyn o bryd a hynny mewn Saesneg yn unig. Rydyn ni wrthi’n gweithio ar fersiwn Cymraeg fel rhan o'r gwaith datblygu. Am y tro, os hoffech gyflwyno adroddiad tor data personol yn Gymraeg,  defnyddiwch y ffurflen sydd ar gael i’w lawrlwytho isod.

The personal data breach online form is currently in beta and only available in English. We are working on a Welsh version as part of its development - for now, if you wish to submit a personal data breach report in Welsh, please use the downloadable form.

You can also report by completing our downloadable form..

Completing a downloadable form / Llenwi ffurflen y gellir ei lawrlwytho

If you have experienced a data breach and need to report it but you’re confident you can manage it without support from the ICO, you may prefer to report it online. You may also want to report a breach online if you are still investigating and will be able to provide more information at a later date.

The online form can also be used to report breaches outside our normal opening hours. 

If you are reporting online please make sure you include the telephone number of someone familiar with the breach, in case we need to follow up with you about any of the information provided.

Personal data breach reporting form (Right click on the link and select 'Save Link As' or 'Save Target as' to download the form before you begin to edit it.)

Ffurflen hysbysu toriad diogelwch data (Cliciwch dde ar y ddolen a dewiswch 'Save Link As' neu 'Save Target As' i lawrwytho'r ffurflen cyn cychwyn.)

We have also created a guide to help you complete the personal data breach reporting form. Right click on the link and select 'Save Link As' or 'Save Target as' to download the guide.

Personal data breach report guide / Cymraeg

What information will I need to provide?

We'll ask you questions about:

  • what has happened;
  • when and how you found out about the breach;
  • the people that have been or may be affected by the breach;
  • what you are doing as a result of the breach; and
  • who we should contact if we need more information and who else you have told.

You should ensure the information provided is accurate and supply us with as much detail as possible. We'll send you a copy of the information you give us. 

What's next?

When reporting a breach, you should give as much detail as possible and be as accurate as you can. We will use the information you provide to decide what should happen next.

We may use it to take regulatory action, or to identify data security incident trends.

Where appropriate, we may share it with law and cybercrime agencies or other regulators. We may also share information with other regulators, such as the Financial Conduct Authority. Where an incident is relevant to another country, we may also share the information with appropriate regulatory representatives in that country. Let us know if you’d like more information about this.

Cyber incidents

Unless you can’t access your system, you should report cyber incidents online.

Where a significant cyber incident occurs, you may also need to report this to the National Cyber Security Centre (the NCSC). To help you decide, you should read the NCSC ‘s guidance about their role and the type of incidents that you should consider reporting.

Incidents that are not considered significant and those that might lead to a heightened risk of individuals being affected by fraud, should be reported to Action Fraud – the UK’s national fraud and cybercrime reporting centre. If your organisation is in Scotland, then reports should be made to Police Scotland.

Where appropriate, the ICO may liaise with the above organisations in relation to the incidents reported to us. However, it is your responsibility to ensure all relevant authorities are made aware of an incident.