Your cart is full, the total is higher than you hoped, and somewhere in the back of your mind is the suspicion that someone else is paying less for the same thing. So you go looking. One friend swears by a coupon extension. Another has been getting cash back for years. Someone on Reddit posts a price chart and tells you to wait a fortnight.
They are all describing different tools that answer different questions. There are four of them worth knowing about: something that tells you whether the price is any good, something that tells you whether it is cheaper elsewhere, something that pays you back after you buy, and something that is already sitting in your banking app doing nothing.
Three of the four work happily together. The fourth is a pick-one, and stacking three of that kind is the single most common mistake people make — they cancel each other out rather than adding up. Here is what to install, and how to use it without losing the money you just earned.
1. Is this actually a good price?
Start here, because the biggest saving available is usually not a percentage off — it is not buying at a bad price in the first place. Plenty of “40% off” is a return to a price that was normal three weeks ago.
Install Keepa (4,000,000 Chrome users, against 800,000 for the alternative). It draws a price-history chart underneath Amazon listings and will alert you when something drops to a price you name. The Camelizer covers the same ground if Keepa’s chart feels like a trading terminal. Either is fine. You only need one, but nothing breaks if you keep both.
These are safe to leave installed alongside everything else on this page. You consult them before you buy; they are not involved in the checkout at all.
2. Is it cheaper somewhere else?
Nothing to install. Chrome and Edge both do this already — price comparison and price tracking are built into the browser you are reading this in. Google describes its version as price history and drop alerts; the cost is that it wants you signed in to Chrome with history syncing on, which is a fair thing to weigh.
One warning, because the naming is genuinely confusing. Edge’s price features are fine to leave on. Edge also has a separate Cashback feature, and that one is a direct competitor to whatever you pick in the next section — Microsoft’s own terms list receiving “cashback or points from a third-party reward program for the same purchase” as a reason you do not qualify. Treat Edge Cashback as one of the options below, not as a bonus on top of them.
3. Can I get money back? Pick exactly one.
Coupon extensions and cashback extensions look like two different products, and every list on the internet treats them that way. They are not. They are the same business.Both are paid a commission by the shop for being the thing that sent you there, and a shop only pays that commission once. Whichever tool was last to raise its hand gets the money; the other gets nothing. That is why you cannot take “the best coupon one” and “the best cashback one” and run them together.
Coupert, which is one of these services, is refreshingly blunt about it in its own help centre: run several and credit goes to only one of them, and “we can’t determine which service will get the credit.” So: one shelf, one choice.
In the US, pick Rakuten. It pays actual cash rather than credit, and you can cash out at $5.01, which is the lowest bar of the group. The honest downside is the calendar: payouts land quarterly, on 15 February, 15 May, 15 August and 15 November, so money can sit for a few months before it reaches you.
In the UK, pick TopCashback. There is no separate Rakuten UK cash back site — rakuten.co.uk simply redirects to the US one — and TopCashback is the most straightforward of the alternatives about why a claim gets declined when it does.
Why not the others, briefly:
- Capital One Shopping pays in gift-card credit, not cash — its terms say the rewards may never be redeemed for cash. It is also the strictest: its terms can disqualify you for merely having a rival extension installed, even unused.
- Karma pays in Coins, and needs 30,000 of them before you can withdraw. At its stated rate of 1,000 Coins to US$1.00 that is $30 — six times Rakuten’s bar — and Coins expire 12 months after you earn them.
- Coupert has three separate expiry clocks on your balance plus a dormancy rule, and publishes no minimum payout at all. The most honest of the group about conflicts, and the most hedged about your balance.
The full ranking is here if you want to see how they compare side by side.
4. Anything from my bank?
Almost certainly, and almost nobody uses them. Amex Offers and Chase Offers live inside your banking app: you scroll a list, tap to activate the shops you actually use, and the credit appears on your statement after you spend. Nothing to install, nothing to remember at checkout.
These add on top of your cashback pick rather than fighting it, because they are settled on your card transaction data rather than on which website sent you to the shop. Different plumbing, so they are not chasing the same credit.
One exception worth knowing: Bank of America. Its deals pagemixes the normal card-linked kind with “Shop Now” deals, which require you to shop through the link it gives you. Those areclick-based, so they are in the same race as your extension. For a “Shop Now” deal, pick one route — the bank’s link or the extension — and leave the other alone.
The stack, in order
This is the whole payoff, and it takes about a minute once it is set up. Three layers that add up, one you choose between.
- Check the price history.Is this actually cheap, or is it just marked “sale”?
- Check whether it is cheaper elsewhere — your browser already offers to do this.
- Activate your one cashback extension before you start filling the cart.
- Check your card’s offers in your banking app for that shop before you pay.
Four ways to lose it after you have earned it
Cash back fails quietly. Nothing warns you; the money just never arrives. These four cover nearly every case.
- Activate first, not at checkout. This is the opposite of what most people do. Rakuten is explicit that you should activate “before you add anything to your cart”, because some shops will not link a purchase to your account if things were in the basket first.
- Only use codes your own service shows you. A code from anywhere else can void the cash back you just activated. That includes the 10%-off welcome code you get for handing over your email address — a real trade-off, not a freebie, so decide which one you would rather have.
- One tab, one session. Finish the purchase in the tab your service opened for you, on the same device. Wandering off and coming back later is the classic way a claim gets declined.
- Gift cards need a quick check. Paying with a gift card can void cash back at someshops but not others — it is usually set per retailer rather than by your extension. Open the shop’s terms and search for the phrase “purchase or redemption”. If it is there, spending a gift card there is excluded too. If only “purchase” appears, paying with a card you already hold is fine.
That is it
A price chart, your browser’s own comparison, one cashback extension, and two minutes in your banking app. The temptation is always to add a fifth thing. In this one corner of the internet, adding more is what costs you money.
The cashback extensions, ranked
| Tool | Best for | Pricing |
|---|---|---|
1 Rakuten | Best overall (US) | Free |
2 TopCashback | Best for the UK | Free |
3 Capital One Shopping | Best if gift cards are fine | Free |
4 Karma | Coins, not cash | Free |
5 Coupert | Weakest of the five | Free |
6 PayPal Honey | Listed for context, not recommended | Free |
See the full comparison: Best Cashback Extensions →
Want the receipts? Our 2026 deep dive on the cashback space quotes the actual clauses behind every recommendation above — the exclusivity terms, the payout arithmetic, the gift-card mechanics and the Honey story.