Privacy policy
Last updated: 13 October 2026
This policy explains how Circadian Signal Ltd (“we”, “us”) uses personal data when you visit circadiansignal.com, join our free guide list, or contact us. It covers the website only. Orders are placed and paid for on our Shopify store, and the store’s own privacy policy applies to that part of the process.
Who we are
Circadian Signal Ltd is registered in England and Wales. Our registered address is 22 Cherry Glebe, Mersham, Kent TN25 6NL. You can contact us at jon@circadiansignal.com or through our contact form. We are the data controller for the personal data described here.
What we collect and why
| Activity | Data we use | Why | Legal basis |
|---|---|---|---|
| Free guide sign-up | Email address, the page you signed up on, and the list tags we apply | To send you the guide and occasional updates about Sleep Through | Consent (you tick by submitting the form). You can withdraw at any time. |
| Advertising measurement (Meta Pixel) | Page views, pages visited, and actions such as viewing a product or starting checkout. Meta cookies (see our cookie policy) | To measure and improve our advertising | Consent. Nothing loads until you accept. |
| Guide sign-up conversion tracking | A hashed (scrambled) version of your email, plus Meta cookie values and your IP address and browser details | To count sign-ups accurately in our advertising | Consent. Only sent if you accept cookies. |
| Contact form | Your name, email address, topic and message | To reply to your question | Legitimate interests (answering your enquiry) |
| Orders and customer accounts | Handled by Shopify on our store: name, delivery address, payment details, order history | To take payment and deliver your order | Contract. See the Shopify store privacy policy. |
| Site security and performance | IP address and request details held by our hosting provider (Cloudflare) | To keep the site secure and running | Legitimate interests |
We do not sell your personal data, and we do not use it for automated decisions. We don’t knowingly collect information from anyone under 18.
Who we share data with
- Shopify: runs our online store, checkout and customer records, and manages the guide list contacts we create there.
- Meta (Facebook and Instagram): receives pixel events and, after you accept cookies, the hashed sign-up event described above.
- Cloudflare: hosts this website and our sign-up and contact services.
- Resend: delivers messages sent through our contact form to us.
- Google Fonts: serves the fonts used on this site. Your browser connects to Google to load them.
Some of these providers are based in the United States. Where data is transferred outside the UK, we rely on the UK–US data bridge where it applies, or the UK International Data Transfer Agreement, as set out by each provider.
How long we keep data
- Guide sign-ups: until you unsubscribe or ask us to delete your details.
- Contact form messages: for up to 12 months after your last reply, then deleted.
- Advertising measurement data: held by Meta under its own retention rules. Cookies expire as described in our cookie policy.
Your rights
You can ask us to access, correct or delete your personal data, to restrict or object to how we use it, or to receive a copy of it. You can withdraw consent at any time, including through cookie settings. To unsubscribe from marketing emails, use the link in any email we send. To use any other right, email jon@circadiansignal.com. We will respond within one month.
If you are not satisfied with our response, you can complain to the Information Commissioner’s Office (ICO) at ico.org.uk.
Security
Our site is served over HTTPS. We only send your data to the services listed above and limit access to the people who need it. No online system is completely secure, so please tell us promptly if you think your information has been misused.
Children
Sleep Through is a supplement for adults. This website is not directed at children, and we don’t knowingly collect data from them.
Changes to this policy
We may update this policy as the site changes. The date at the top shows when it was last revised.