The Browser Extensions Every Stacker Should Install
This is general advice, not a measurement of any particular store or portal.
A no-fluff list of the cashback, coupon, and price-history extensions worth keeping in your toolbar — and the ones to delete.
Why extensions matter
A stacker's extensions automate the easy-to-forget steps: portal click-throughs, code testing, and price-history checks. The right combination handles those steps in the background so you don't have to remember to open a tab.
Cashback portal extensions
These are the most valuable extensions in the category because they convert "I forgot" into "one click."
Coupon-testing extensions
The codes are often weaker than what a manual search turns up on Promo Sweeper, but the auto-testing flow takes 8 seconds and routinely finds at least one working code on big-box retailer carts.
Price-history extensions
The number of fake sales these tools surface in the wild is genuinely alarming.
Receipt and warranty trackers
Without an automated tool, almost no one claims them.
Extensions to think twice about
Only install extensions from publishers you can verify, and audit your active extensions every quarter.
How to set them up to coexist
When two extensions both want to handle the cashback prompt, the last one installed usually wins. Set up the cashback portal you actually use first, then add coupon-test and price-history tools after. If you see a generic "this site has cashback!" popup that's not from your real portal, disable that extension immediately.
Where to go next
- How to Stack Coupons and Cashback (The Complete 2026 Guide) — The full Promo Sweeper playbook for combining promo codes, cashback portals, store credit, and rewards cards into one checkout flow.
- — A side-by-side comparison of the three cashback portals every US shopper should keep installed — base rates, payout cadence, and best-fit retailers.
- The Best Cashback Credit Cards for Stacking on Top of Promo Codes — How to pick the credit card layer of your stack — by category bonus, annual fee, and portal compatibility.
- The Free Shipping Loophole Guide — How to Hit the Threshold Without Filler — Practical tactics for clearing free-shipping minimums without buying things you don't need or paying for shipping at all.
- The Holiday Deal Calendar — When Each Major Retailer Drops Its Best Codes — A month-by-month look at when the best discounts hit at major US retailers, so you can time your bigger purchases.