Quick answer

Start in September or early October, before sellers begin moving prices for the season. A chart you open in November already includes the run-up, so the ordinary non-sale price you need is no longer visible. Whatever the banner claims, a history that only begins a few weeks ago cannot settle anything.

Table of contents

What the chart is actually telling you

The useful answer to when to check a price history before Black Friday UK is not a date on its own. It is a condition: be looking early enough that you own the ordinary, non-sale number the item sat at before anybody started preparing for the season.

By late November that number has gone. Whatever the seller did to the price in October is already inside the line you are looking at, and a discount measured from a base that moved is not a discount. Reading the chart takes about ninety seconds an item.

The shapes worth recognising

Open a twelve-month chart for one listing and it will usually look like one of these.

  • Flat, with short dips every few weeks. The item goes on offer regularly, so November is one chance among several. No urgency, and no reason to accept a mediocre price on the day.
  • One deep trough months ago that never came back. Most likely a clearance run or a pricing error. Holding out for it is how people spend a year not buying something they wanted.
  • A step up in the base a few weeks before the season, then a "discount" from the new level. This is the shape the page exists for: the sale price can still sit above what the listing held all summer.
  • A long slow decline. An ageing model on its way out. The sale is roughly the drift you would get by waiting, so the question becomes whether a successor is due.
  • A line that only starts a few weeks ago. Nobody was tracking that listing before you arrived, so it cannot tell you anything yet. That is the argument for September.

Two gaps, and only one of them matters

Every tracker shows the distance between the current price and the lowest price ever recorded. That is the less useful of the two numbers. The gap worth reading is between the current price and the twelve-month average.

An all-time low is a single event that may never repeat; the average is where the listing lives. Set your target from the average and treat the low as a bonus.

What a price chart cannot see

A tracker follows a listing, not a product, and the two come apart more often than you would expect.

  • The listing changes underneath the chart. A variant swap, an added bundle or a new model year leaves the line looking continuous when the product has changed.
  • The seller changes. On a marketplace the cheapest figure can belong to a third party rather than the retailer, with a different returns route.
  • Delivery sits outside the tracked figure. Put your own postcode in first: surcharges for the Scottish Highlands, the islands and Northern Ireland appear at checkout.
  • Stock is invisible. A price nobody can buy is not a price, and an alert cannot tell the difference.

Where the coverage runs out

Amazon is the easy case. Dedicated trackers such as CamelCamelCamel and Keepa chart Amazon UK listings over time, including the third-party sellers on the same listing, so a twelve-month view is usually available.

Currys, Argos and John Lewis are a different job. Amazon-specific trackers do not follow them, so you are relying on multi-retailer comparison sites such as PriceSpy, PriceRunner or Idealo. Those keep price history too, but coverage varies by retailer and product, so check yours is listed.

A "was" price is a claim, not a reading

UK consumer protection rules require a reference price to be a real previous selling price rather than a decorative one, and the Competition and Markets Authority can act on misleading reference pricing. That helps little at the moment of the ask: nothing on the page lets you check whether the higher figure ever ran. Your own recorded history can.

September to January, one month at a time

Retailer behaviour varies year to year and by category, so read this as the shape of the season, not a schedule. Three dates below are calendar facts; the rest is a pattern, and the rule never changes: compare against your own recorded number, not against what the page says today.

September: this is the whole job

Nothing is on offer and nothing needs buying, which is why September matters. It gives you the one thing November cannot: a baseline nobody was preparing for.

Write down the exact listings you care about, today's price, today's date, and the twelve-month average and low from whichever tracker covers that retailer. Three or four items is plenty. If you are kitting out a room rather than replacing one item, settle the full list now: our home office desk kit guide is the sort of list to fix before the season, because choosing under sale pressure is how bundles win.

October: watch the base, not the banners

October is when the base price starts to move on some listings, and catching that movement is the reason you did September. Compare against your own note, not against today's page.

Amazon runs a members-only sales event in the autumn that muddies the water for a fortnight either side: prices dip, come back, and settle somewhere that is not necessarily where they started. Do not let an event price become your baseline.

Retailers announce their own November windows through October, which our guide to when Black Friday tech deals start in the UK covers. This page is about the number you bring with you.

Early November: stop adding items

By the first week of November your baseline is as good as it is going to get, and adding an item now means starting its history from inside the run-up. Set your alerts this week, at the figure you decided in September rather than one that looks plausible against today's page.

Black Friday week, up to Friday 27 November

Black Friday 2026 falls on Friday 27 November. Discounting starts well before it and arrives in uneven steps rather than on one morning, so refreshing all week is a poor use of it.

When an alert fires, open the chart, confirm the listing is still the same product from the same seller, then compare against your September number. Not the percentage, and not the crossed-out figure beside it.

Cyber Monday, Monday 30 November

Cyber Monday 2026 falls on Monday 30 November. Neither day has a dependable edge over the other, which is the case for a target number rather than a target date. If nothing has met your number by Monday evening, that is information rather than failure.

December: what still moves, and what stops mattering

Prices keep moving in December, but the constraint shifts from price to logistics: a better number that arrives after the day it was needed is worth nothing. For anything with a date attached, buy earlier and accept a worse number, and check the retailer's guaranteed cut-off rather than a courier's general one.

Boxing Day, Saturday 26 December, and January

Boxing Day 2026 falls on Saturday 26 December, and the clearances that follow lean towards outgoing stock, so the better price often lands on last season's model rather than the one on your list. Useful if you were flexible, useless if you were not.

Your September baseline still applies in January. Our guide to whether anything is left in the Boxing Day sales covers what actually moves after Christmas.

The order to do this in

One sitting, three or four items, about half an hour. Do it in September and November becomes a five-minute job.

  1. Pick the exact listing. Full model number, the specific variant and colour, and a note of who is selling it. A model number only one retailer stocks cannot be compared against anything, which is worth noticing.
  2. Record today's price and today's date. The step people skip, and the one that makes everything after it work. A dated note now is worth more in November than any chart you can dig up then.
  3. Note the twelve-month average and the twelve-month low. Both, with the date the low happened. A low the item held for a fortnight is a repeatable price; a low it touched for one day is a story.
  4. Decide your number before the season, and set the alert there. An alert set at "whatever the sale offers" is not an alert, it is a notification.
  5. Re-check the listing identity in November. Before you pay, confirm the model number, variant, bundle contents and seller match what you wrote down. Thirty seconds, and it catches the most expensive mistake on this page.

CamelCamelCamel and Keepa both chart Amazon UK price history and can email you when a listing reaches a figure you choose. For Currys, Argos, John Lewis and the rest, a comparison site such as PriceSpy, PriceRunner or Idealo is the route in.

For three or four items we would skip the extensions and keep a note on the phone: item, link, date, price, twelve-month average, target. Same information, survives a change of browser, no maintenance. Extensions start paying off at a dozen listings, not four.

Where this goes wrong, and how to recover

Anchoring on the all-time low. The costliest failure: it costs you the purchase, not money. If the low happened once, on a listing that has changed since, it is history, not a target. Reset against the twelve-month average and buy.

Tracking the wrong listing. Wrong variant, wrong capacity, wrong bundle, or an Amazon listing whose identifier now carries a different product. The recovery is step five.

Believing a reference price that never ran. If your own history shows the item sitting below the crossed-out figure for most of the year, that figure describes the marketing rather than the market.

Assuming the extension covers everything. An Amazon tracker showing no data for a Currys listing is not evidence that Currys has not discounted. It is evidence you are looking in the wrong place.

Letting an alert fire on a marketplace seller. The alert watches the lowest price on the listing, and that price can belong to a seller with a slower delivery window and a different returns route. Read the sold-by line at checkout.

Buying, in the sale, something you would not have bought at all. No chart protects you from this. The defence is the September shortlist: if it was not on the list before the season, it is a purchase a countdown timer talked you into.

Frequently asked questions

Is it too late if I only start checking in November?

It is late, but not useless. You have lost the clean pre-season baseline, so the chart already contains whatever happened in October. Read the twelve-month average rather than the recent weeks, and set your target from the summer part of the line.

How far back does a price history need to go before I trust it?

Twelve months is the working minimum, because it covers a full turn of the season you are standing in. A chart with three months behind it only shows the run-up, which is the period you can learn least from.

Do I need a browser extension, or will a note on my phone do?

For three or four items, the note wins: item, link, date, price, twelve-month average and target is everything you act on. Extensions earn their place when the list is too long to check by hand.

Does any of this work for Currys, Argos or John Lewis?

Yes, but through different tools and with thinner data. Amazon-specific trackers do not follow those retailers, so you need a comparison site such as PriceSpy, PriceRunner or Idealo. Check your product and retailer are listed, because coverage varies.

Is the lowest price ever recorded the one to hold out for?

No, and treating it as a target is the most reliable way to end up buying nothing. Use the twelve-month average as your reference and the low as context. If it happened once and never came back, it was probably a clearance or a pricing error.

Should I wait for Boxing Day or January instead?

Sometimes, if you are flexible about the exact model. Boxing Day 2026 falls on Saturday 26 December, and the clearances that follow lean towards outgoing stock, so the deeper cuts often land on last season's version.