Know whose price changed — and what it means for your margin.
Not all price changes are the same problem. A competitor undercutting you, your own listing price shifting unexpectedly,
and the Buy Box price moving are three different events — each requiring a different response.
SentryKit tells you which one happened, who caused it, and whether acting would breach your floor.
Your price, competitor's price, Buy Box price — one alert type, three distinct signals
20+
alert types watching every layer of your listing simultaneously
Floor check
every price alert shows whether matching the new price breaches your floor
30 days
Free trial — full price monitoring from day one, no credit card
A Critical Distinction
"Price changed" means three completely different things. SentryKit tells you which one.
Most tools send one notification: price changed. That's useless without knowing whether it was your price,
a competitor's, or the Buy Box price — because each one requires a completely different response.
Matching a competitor who undercut you is a pricing decision.
Correcting your own listing that shifted unexpectedly is an operations fix.
And if the Buy Box price changed with no competitor move, the cause is on your end — and matching won't fix it.
Your Price Changed
Your listed price shifted — and you didn't do it.
Flat file upload error, Amazon applied a promotional price, or an unauthorized listing edit.
Your price is now wrong. Every sale at the new price is potentially at the wrong margin.
This is an operations problem, not a competitive one.
Alert includes
Old price / New price / Exact dollar changeTimestamp of the changeWhether Buy Box ownership shifted as a result
Competitor Price Drop
A competing seller just dropped below your price.
Another seller on your ASIN lowered their price. Depending on the gap and their fulfillment type,
this may or may not threaten your Buy Box. The floor breach check tells you immediately
whether matching is even an option without going negative.
Alert includes
Their new price / Your current price / Gap to closeWhether matching breaches your floorTheir fulfillment method
Buy Box Price Changed
The Buy Box price moved — check whether you still hold it.
The Buy Box-winning price changed. This could mean a competitor won it at a new price point,
or that your own repricing shifted the Buy Box price. Either way you need to know who holds it
now and at what price before deciding anything.
Alert includes
New Buy Box price / Previous Buy Box priceCurrent Buy Box holderWhether you hold it or lost it
Amazon doesn't categorise these three events differently — it's all just "a price change."
SentryKit fires a distinct alert for each because the data you need and the action you take are completely different.
For the full breakdown of what actually decides Buy Box eligibility beyond price, see How to Win the Amazon Buy Box in 2026.
The Alert
Here's exactly what lands in your inbox — with everything you need to act.
SentryKit doesn't just tell you a price changed. It tells you
which event fired, who caused it, whether acting would breach your floor,
and what the right response is — so you can decide before leaving the alert.
Competitor Undercut
🥗
BAMBOO SALAD BOWL SET 3-PIECE
US MARKETPLACE · BRAND: GRAINHAUS · ASIN: B09XKRTLM5
COMPETITOR PRICE DROP · FLOOR BREACH RISK
Competitor dropped below you — matching puts you below floor
THEIR PRICE
$21.99
Competitor
YOUR PRICE
$27.99
Active listing
GAP
$6.00
To close
FLOOR STATUS
−$1.50
Below your floor
Seller Profile · Pro
Seller: QuickShip Co.
Fulfillment: FBA
Feedback: 96% (4,200 ratings)
Account Age: 4 years
Matching $21.99 puts you $1.50 below your floor — hold or reassess your cost structure Floor: $23.49
Your Options
A
Hold your price. Matching breaches your floor by $1.50. An established FBA seller at 96% feedback is a real competitor — but selling at a loss isn't the answer.
B
Review your cost inputs. If your floor feels wrong, check whether your COGS or FBA fee inputs are current. A stale floor is a false constraint.
C
Monitor their pricing pattern. Established competitors often test lower prices and pull back. Log this event — if they hold the Buy Box for 48h+, then reassess.
Your Price Changed
💧
STAINLESS STEEL WATER BOTTLE 32OZ
US MARKETPLACE · BRAND: HYDROEDGE · ASIN: B08QLPKMVX
YOUR LISTING PRICE CHANGED · INVESTIGATE BEFORE ACTING
Your listed price shifted — this was not a competitor move
OLD PRICE
$32.99
Previous
NEW PRICE
$24.99
Current
CHANGE
−$8.00
Unexpected drop
BUY BOX
✓ Held
Still yours
Your price dropped $8.00 unexpectedly. You still hold the Buy Box — but at a margin you didn't intend.
Check your Seller Central for flat file errors, promotional pricing rules, or unauthorized edits
before making any further price changes.
Your Options
A
Check Seller Central immediately. Go to Manage Inventory — look for a promotional price or sale price applied automatically. Remove it if unintended.
B
Review recent flat file uploads. A bulk price update may have overwritten your intended price. Check the upload log in Seller Central.
C
Correct and monitor. Reset your price to the intended amount and watch for the next 24 hours to confirm it holds.
Know whose price changed — before it costs you the Buy Box.
All 20+ alerts · 30-day free trial · No credit card required
The alert tells you what happened. Here's how sellers act on the data.
SentryKit's Price Change alerts are designed to make the next step obvious — not leave you guessing.
The path splits the moment the alert fires based on which event occurred.
Competitor Undercut — Recovery Path
1
Check the floor breach indicator first.
The alert tells you whether matching their price is above or below your floor.
If below, do not match. Selling at a loss to hold the Buy Box is never the right move.
Check Amazon's guidance on
how fulfillment method affects Buy Box allocation
— an FBM seller at the same price may not win it anyway.
2
Assess their fulfillment method.
An FBA seller near your price is a real competitive threat. An FBM seller at the same price
has a fulfillment disadvantage. The alert shows their method so you can weigh it correctly
before making any price move.
3
Decide: match, hold, or adjust.
If within floor: assess whether a price move recovers the Buy Box, weighing their fulfillment method and account standing.
If below floor: hold and monitor. A sustained competitor at a below-floor price is a signal to review your cost structure — not to match immediately.
If the gap is large and they're FBA: review your cost structure and pricing strategy before making a long-term decision.
4
Confirm Buy Box outcome before touching ad spend.
Only resume Sponsored Products once you confirm you've reacquired the Buy Box.
Running ads when you don't hold it means paying for clicks that convert to a competitor.
SentryKit's price timeline shows you when your position stabilises.
Your Price Changed — Recovery Path
1
Go to Manage Inventory in Seller Central now.
Check whether a promotional price, sale price, or business price rule was applied automatically.
These are the most common cause of unexpected price drops on your own listing.
Open Manage Inventory in Seller Central →
2
Review recent flat file uploads.
If you or a team member uploaded a bulk price update recently, it may have overwritten your intended price.
Check the Upload Status report for recent activity.View Upload Status in Seller Central →
3
Check for unauthorized listing edits.
If neither of the above explains the change, check your listing change history in Seller Central.
An unauthorized contributor or a hijacker who gained editing access may have changed your price directly.
If you suspect unauthorized access, review your account permissions immediately.
4
Correct the price and verify it holds.
Reset to your intended price, confirm it appears correctly on the product page,
and monitor the next alert cycle to ensure it doesn't revert.
SentryKit will fire again immediately if the price changes a second time — so you'll know the moment it happens.
How It Works
Three price events. One alert type. Always with the floor breach check.
SentryKit's Price Change Alert tells you more than that a price moved — it tells you which direction,
whose move it was, and whether responding would cost you margin.
💰
Your price, their price, Buy Box price — separated
Most tools fire one price change event. SentryKit distinguishes between your listing price changing,
a competitor's price dropping, and the Buy Box price shifting —
because the response to each is different.
🛡️
Floor breach check built into every event
Every price change alert shows whether the new competitive price is above or below your floor.
Know before you react whether matching is even viable — not after you've already dropped your price.
📈
Full price timeline per ASIN
Every price movement is logged with a precise timestamp. Identify competitor pricing patterns,
catch recurring floor-testers, and document pricing events for Brand Registry cases.
✓
30-day free trial — no credit card
Full price monitoring across your entire catalog from day one.
Starter plan from $19/mo. Pro from $49/mo.
No ASIN limits — monitoring scales with your order volume.
All SentryKit alerts — 20+ signals, every layer of your listing
A price change alert is a notification that fires when a price event occurs on a monitored ASIN. SentryKit distinguishes three types: your own listed price changing unexpectedly, a competing seller dropping their price below yours, and the Buy Box price shifting. Each fires a separate alert because each requires a different response.
The most common causes are: a promotional or sale price applied automatically by a pricing rule, a bulk flat file upload that overwrote your intended price, or an unauthorized listing edit. SentryKit's Price Change alert fires the moment your listed price changes and logs the old and new price with a timestamp so you can trace the cause immediately.
No. Amazon does not send price change notifications to sellers — not for your own price and not for competing sellers. The only native way to know is to check each listing manually in Seller Central. SentryKit monitors every tracked ASIN continuously and fires an alert as soon as any price event is detected.
SentryKit's Price Change alert shows you the exact gap between the competitor's price and yours, and whether matching would put you above or below your price floor. If matching breaches your floor, the alert tells you explicitly — so you don't have to calculate it manually under pressure. If you're above floor, assess their fulfillment type; an FBM seller at the same price has a fulfillment disadvantage in Buy Box allocation.
Manual monitoring means checking one ASIN at a time, only when you're at your desk, and only catching changes that happened to occur during a check. SentryKit monitors your full catalog continuously and fires the alert the moment a price event is detected — with old price, new price, who changed it, and the floor breach status. You get the intelligence before the Buy Box shifts, not after.
Start a 30-day free trial at live.sentrykit.com/signup — no credit card required. Connect your Amazon Seller Central account and SentryKit begins monitoring all your ASINs for price events immediately.
Start a 30-day free trial and connect your Seller Central account — SentryKit begins monitoring every tracked ASIN for price and listing-edit activity immediately, with no rules to configure first. Competitor Price Change alerts fire with your chosen delivery cadence, real-time or digest, while listing-edit signals like the Product Details Change Alert flag unauthorized changes to your title, bullets, description, or images. Together they give you one dashboard covering both what competitors are doing to your Buy Box and what's changing on your own listing.
SentryKit's Daily Portfolio Digest rolls up your alerts — price changes, competitor undercuts, Buy Box shifts, and more — into a single daily summary, so reviewing your account becomes one checklist instead of clicking into Seller Central ASIN by ASIN. Anything urgent still fires as a real-time alert the moment it happens; the digest is there for everything else you want to review once a day, on your schedule.
SentryKit's Competitor Price Change alert fires the moment a competing seller on your ASIN moves their price — you choose whether it lands in real time or in your daily digest. There's no repricing rule to configure first: connect Seller Central and every tracked ASIN is covered from day one. The alert includes the competitor's new price, the gap to yours, and whether matching it would breach your price floor, so you're deciding with numbers instead of a gut check.
Every price event SentryKit detects — yours, a competitor's, or the Buy Box price — is logged with a timestamp, so you can see the pattern of a competitor's pricing behavior instead of just the latest snapshot. That history is what tells you whether a price drop is a one-off test or a sustained undercut worth responding to. SentryKit doesn't replace your repricer or set prices for you — it gives you the competitor visibility your repricing decisions, manual or automated, are actually based on.
