Privacy

What we keep

Your email address, so we can send you a sign-in link and tell you when a price drops. And for each purchase we are watching:

• the item number
• the price you paid, and the regular price if the receipt showed one
• any money already taken off at the register
• how many you bought, and the date
• the warehouse number, country and state or province

That is the whole list. It is the same list whether you type a purchase in by hand or let the browser add-on read it from your Costco account.

What we never receive

• your receipts
• the name or description of anything you bought
• your membership number
• how you paid — no card number, no last four digits
• your Costco password, or the sign-in code your browser holds for Costco

This is not a promise about how carefully we handle those things. We do not have them. The browser add-on reads your receipts on your own computer, keeps the handful of numbers above, and throws the rest away before anything is sent.

The browser add-on

It runs on two web addresses only — costco.com and costco.ca — plus the address Costco's own pages use to fetch your receipts, and our own address. It cannot see any other website you visit. It reads your receipts using the sign-in you already have with Costco; that sign-in never leaves your computer.

The add-on contains no downloaded code. Everything it runs is in the package you installed, and it never fetches a program from anywhere to run it.

Until you ask for emails, nothing is sent to us at all. The list sits on your own computer.

What we do with it

One thing: we compare the items you bought against the sale prices Costco is currently advertising, and email you when one of them is worth money back. We do not sell anything to anybody, we do not share your information with advertisers, and there are no trackers on this website.

How long we keep it

Costco's price adjustment window is 30 days, so a purchase stops being useful to us shortly after that and is removed. Your email address stays until you delete your account.

Deleting everything

There is a Delete everything button on your account page. It removes your email address and every purchase, straight away, and signs you out everywhere. There is no undo, and nothing is kept in a backup copy for us to restore.

You can also stop the emails without deleting anything — every email we send has a one-click link at the bottom, and it works without signing in.

Who to ask

Email privacy@engsight.app with any question about this page, including a request to see or delete what we hold.

Not affiliated with Costco Wholesale.