Imagine waking up one morning, checking your Amazon seller dashboard, and noticing something odd. Your best-selling item is now split into two different listings. Uh-oh. One has your reviews, and one doesn’t. Worse? Your Buy Box is gone. Welcome to the chaotic world of Amazon’s automatically-split ASIN files!
TL;DR
Amazon sometimes splits ASINs when it believes duplicate listings exist. This causes one product to be split into two or more listings, losing reviews, history, and sales traction. Sellers can resolve this by identifying the root duplication, submitting proof to Amazon, and requesting a merge. It’s frustrating—but fixable with persistence and strategy!
What Does “ASIN Split” Mean?
Let’s break it down. ASIN stands for Amazon Standard Identification Number. It’s what Amazon uses to track products. When a product seems duplicated—maybe because of slight changes in title, brand spelling, or variation issues—Amazon might “split” the ASIN.
That means your original listing becomes two or more separate products. Each with a different ASIN. Each starting from scratch.
Why Is This a Problem?
A split ASIN isn’t just annoying. It can hurt your business.
- You might lose your reviews.
- Your bestseller rank could vanish.
- The new listing may not win the Buy Box.
- Customer questions and answers get lost.
And if other sellers jumped on your original listing, they may now appear on the new version too. Confusing, right?
Okay, How Do ASIN Splits Happen?
Usually, it’s not your fault (but sometimes, it kind of is).
- Amazon’s system detects two listings that seem “too similar.”
- There may be small changes: title, color description, or even punctuation.
- If you or another seller updated the listing data with discrepancies, that can trigger it.
- Selling the item under different UPCs or EANs can also lead to splits.
Once Amazon thinks two listings are “duplicates,” it may decide to separate them if it believes they aren’t the same exact product.
Step-by-Step: What Sellers Did to Fix It
Fortunately, many sellers shared their strategies on how they successfully got their ASINs merged again. Let’s go step-by-step with what worked for them.
1. Confirm the Problem
First, make sure an ASIN split actually happened.
- Search for your product on Amazon.
- Look for duplicate listings—same product, different ASINs.
- Check if reviews were moved or retained only on one version.
If you see your product appearing multiple times with slightly different data, you probably have a split ASIN situation.
2. Gather All Evidence
You’ll need to show Amazon that this is the same product. Sellers said having organized data helped A LOT.
- Take screenshots of both listings side-by-side.
- Include UPC/EAN info. It should match (or be explainable).
- If you own the brand, include your authorization and brand registry info.
- Provide invoices or product packaging photos to prove similarity.
3. Open a Case in Seller Central
Now, it’s time to talk to Amazon support.
Go to Seller Central → Help → Get Support → Products → Fix a product page → Merge duplicate listings. Then, explain what happened. Keep it short and sweet. Mention that you believe the ASIN was automatically split.
Example message:
“Hello, I’ve noticed that our product was automatically split into two ASINs. Both ASINs refer to the same product, and we believe this was a duplicate listing error. Please help merge ASIN B00XXXX with ASIN B00YYYY. Attached are images, UPCs, and evidence that they are the same item. Thank you!”
4. Be Patient… but Persistent
Sometimes, Amazon’s first response will be a template. Don’t panic. It’s normal.
If they reject the case, open a new one, or respond to the existing one with more evidence. Keep your tone polite, professional, and consistent.
Some sellers reported success only on the third or fourth ticket.
5. Ask for Catalog Team Involvement
If things aren’t progressing, specifically ask for the case to be escalated to the catalog team. They’re the ones who handle merges and listing corrections.
Sellers said their chances went up once the catalog team took over, especially if they had:
- Brand Registry
- Invoices from the manufacturer
- Clear documentation of duplicate listings
6. Celebrate (or Repeat)
If Amazon agrees, they’ll merge the ASINs. Reviews may take a few days to reappear, but they usually do return. Traffic will gradually shift back to the original ASIN.
But if Amazon doesn’t approve, try again. Adjust your evidence and keep refining your message. Many sellers said that persistence is key.
Tips from Sellers Who’ve Been There
- Use flat files: If you manage many listings, using Excel flat files can help maintain data consistency.
- Keep a revision log: Write down any major listing edits you make, including date/time and account used.
- Limit backend field changes: Frequent edits to product descriptions, titles, and attributes can trigger algorithmic flags.
- Enroll in Brand Registry: This gives you more power to manage listing content and get faster support.
How to Prevent Future Splits
No one wants to go through that again, right? Here’s what to do to reduce future issues:
- Ensure consistent titles, bullet points, and attributes.
- Use the same UPC for the same product across marketplaces.
- Don’t create a new listing for a product that already exists in the catalog.
- Monitor listings weekly to catch problems early.
Final Thoughts
An ASIN split can feel like Amazon turned your world upside down. But it doesn’t have to be a total disaster.
Sellers have fixed it—with screenshots, invoices, and patience. The key is to stay calm, document everything, and talk to the right teams.
And remember, you’re not alone. Many sellers have faced (and conquered) the ASIN split mystery. Now you can too!
