Seasonal

Rates on shopping portals, the sites that pay you for starting your online purchase there, are not random. They climb around the moments when stores compete hardest for orders: Black Friday and Cyber Monday above all, the wider stretch either side of them, the big mid-year sale events, and back-to-school in late summer.

This topic is that calendar, plus the caveats that keep it useful. Around the big sale weeks, plenty of stores' ordinary rates get lifted for a few days at a time, and those lifts cluster. Knowing which weeks they cluster in is worth real money on a purchase that can wait - and worth saying plainly: this is the first holiday season our own tracking will see live, so the calendar leans on how these events are run, not on a chart of last year's numbers.

What a calendar cannot do is promise that a particular store's rate will be lifted on a particular day. Which stores and which categories get included changes from one event to the next, and portals run their own one-off promotions whenever they like, with no notice at all. So use the calendar to know which weeks are worth checking, and let the store's own rate history tell you whether today's number is actually good.

The practical version, if you shop seasonally: set an alert on the stores you already know you are buying from, and let the email find you when one moves. That beats checking every day, and it beats missing the week entirely.