Privacy policy
PropertySieve browser extension and propertysieve.com · last updated 31 October 2026
PropertySieve has no user accounts, no ad networks or ad tracking, and no analytics. This page explains exactly what stays on your device, what our server is asked for, and what is shared anonymously.
Who we are
PropertySieve is a trading name of Popsall Ltd, registered in England & Wales, No. 16953262. Registered office: 3rd Floor, 86-90 Paul Street, London EC2A 4NE. Popsall Ltd is the data controller for the information described on this page, and is registered with the Information Commissioner's Office (registration ZC164232).
What stays in your browser
Your sieve (filters, words and places), Rightmove filters, journeys, shortlist, ruled-out homes, notes, and the
history of homes and prices you have seen are stored by your browser on your device
(chrome.storage.local). They are not uploaded. You can export them to a file, and
import that file again, from the extension.
What our server looks up for you
To show house facts (sold prices, energy certificates, floor area, value against local sales,
flood zones, planning and broadband), the extension asks our server at
propertysieve-data.propertysieve.workers.dev, run on Cloudflare. For a listing, a request
contains its postcode, the portal's display address, property type, bedrooms, stated floor area,
map pin and the portal's listing id. It contains nothing that identifies you. Our server looks these
up in public records (HM Land Registry, the Energy Performance Certificate register, the UK House
Price Index, Ordnance Survey, the Environment Agency, planning.data.gov.uk, Ofcom and postcodes.io),
sending those services only the postcode or address being looked up. Answers are cached by postcode
to keep the service fast. We do not keep a record of who asked.
On a Rightmove listing page the extension also sends the listing's own description and up to four of its photos (shrunk) to our server, which asks Cloudflare Workers AI two questions: how the listing describes the home's condition, and whether a house number or name is legible in the photos. Only the answer is kept, against the listing; the text and photos are not stored. Photos are never checked for a listing whose map pin the portal shows as approximate.
Once a week, for homes on your shortlist that went under offer, sold subject to contract or off the market more than a month ago, the extension asks our server whether HM Land Registry has registered the sale. The request is a list of portal listing ids, shuffled together with at least as many other such listings you have seen, so it cannot be read as your shortlist. It carries no licence key or other identifier, and our server stores nothing from it.
For a home you shortlist, the extension asks our server for planning applications nearby. The request carries only a location rounded to about 200 metres, with no licence key or other identifier, so it cannot tie you to the home; the exact list is worked out in your browser. Our server keeps the applications themselves (public records from council planning registers, collected by UK PlanIt), not who asked.
If you add a Plus licence key, the extension checks it with our server now and then. That check carries the key and nothing about what you browse. While you have a key, house-fact lookups carry it, so our server can tell a Plus lookup from a free one; it does not record which listings a key looked up.
What is shared anonymously (and how to stop it)
- Price sightings. When sharing is on (the Settings tab on the PropertySieve toolbar), the extension sends the listing id, the asking price and the day it was seen, with no identifier for you or your device. These build the price histories everyone sees. Turn it off at any time.
- Market status changes. When sharing is on and a listing you see goes under offer,
sold subject to contract or off the market (or comes back), the extension sends the listing id, the
status and the day. For those homes it also sends the postcode, property type, bedrooms, the Royal
Mail delivery point the portal shows, and our best guess at which house it is (with the evidence
behind the guess). Months later our server matches the agreed sale to its HM Land Registry price,
so asking prices can be compared with sold prices. If the portal shows the map pin as approximate,
a house you pick yourself is never sent.
This is information about a property, not about you: the address guess is a reference to a public address record, and sold prices are published by HM Land Registry. We keep it to work out how asking prices compare with sold prices (shown as figures for a street or area) and, once a sale is registered, to match that listing and later listings of the same home to the right address. We never use it to name the address behind a listing whose map pin is approximate. Anyone with a question about a property's record can contact us below. - House confirmations. When sharing is on and you pick which house a listing is, the listing id and the chosen address reference (UPRN) are sent, so other users get a better match.
Other network requests
- The portal you are browsing (rightmove.co.uk or onthemarket.com), using your existing session, to read listing and search pages you could open yourself. If you turn on background checks, this also happens while Chrome is open: every 2 hours for your shortlist (on unless you turn it off) and every 30 minutes for your saved searches (if you turn it on).
- propertysieve.com, to check whether a newer version is available.
- OpenRouteService (api.heigit.org, HeiGIT, Heidelberg), only if you add your own API key for journey times: your saved destinations and listing coordinates are sent to compute them.
Like any website, our server and propertysieve.com receive your IP address with each request as part of how the internet works. We do not store it alongside anything you send.
Bug reports
PropertySieve keeps a short log of its own errors in your browser (the last 30, with web addresses, listing ids, postcodes, email addresses and keys removed as they are recorded). Nothing is sent unless you press Report a bug and then Send report. A report contains what you write, the extension version and browser, and, if you leave the box ticked, that error log plus counts and switches (how many homes are remembered or shortlisted, whether background checks and sharing are on, whether a routing or licence key is set, never the keys themselves). You can see exactly what will be sent before sending. Your email address is included only if you type it for a reply. To stop one person flooding us we keep a fingerprint of your IP address that changes every day and cannot be turned back into the address. Reports are deleted after 30 days; after that only a count per error type is kept, with no text.
Third parties
We do not sell or share personal data. Cloudflare hosts our server and website. The public data services listed above receive only the postcode or address being looked up.
Your choices
Turn sharing off in the Settings tab on the PropertySieve toolbar. Remove the extension and Chrome deletes everything it stored on your device. Shared price sightings, status changes and confirmations carry no link to you, so they cannot be traced back to you or deleted individually.
Contact
Questions: hello@propertysieve.com.