Amazon Sell-Through Rate: How to Calculate and Raise It

1. What Is Amazon Sell-Through Rate?

Sell-through rate is the percentage of your FBA inventory that sold over the last 90 days compared to your average on-hand stock during that window. Amazon calculates it on a rolling 90-day basis. It measures how efficiently you use warehouse space.

Fast-moving stock earns you more capacity. Slow stock generates fees and cuts it. Sell-through feeds into your IPI score, which determines your storage capacity and aged inventory exposure.

If you are working on scaling your Amazon FBA business, sell-through rate is one of the first things to get under control. It affects how much you can send in, how much you pay in fees, and how Amazon scores your account overall.

2. How Amazon Calculates Sell-Through Rate

The formula: units sold in the last 90 days divided by average units on hand over that same 90-day period. Multiply by 100 to get a percentage.

Example: you sold 75 units in 90 days and your average on-hand inventory over that period was 100 units. 75 divided by 100 equals 0.75. Your sell-through rate is 75%.

Amazon also expresses this as an annualized number in some dashboard views. A 90-day rate of 100% equals a 400% annualized rate. That 400% benchmark Amazon references means you sold through your average on-hand stock once in 90 days.

3. What's a Good Sell-Through Rate on Amazon?

Amazon considers a 90-day rate of roughly 100% (annualized: 400%) the baseline for healthy inventory. You are selling through your average on-hand stock within a 90-day window.

For online arbitrage, I target at least 100% on a 90-day basis for every ASIN I stock. That is my personal floor. Products I expect to move slower get smaller buy quantities, or I skip them if the margin does not justify the storage risk.

Below 50% on a 90-day basis is a red flag. That means you are carrying more than six months of supply at your current sales pace. Aged inventory surcharges start at 181 days, so any ASIN under 50% sell-through is already on the clock.

4. Where to Find Your Sell-Through Rate in Seller Central

Go to Inventory in Seller Central, then FBA Inventory. There is a "Sell-Through" column in the inventory table. Amazon color-codes it: green means healthy, yellow means watch it, red means act now.

You can sort by sell-through rate to find your worst performers instantly. Click the column header, sort ascending, and your slowest movers are at the top. That list is your weekly action plan.

The Inventory Performance dashboard also shows sell-through as one of the four scoring inputs for your IPI score. Check both views. The ASIN-level view shows where to act. The dashboard shows how your overall account looks to Amazon.

5. Sell-Through Rate vs. Sales Velocity: The Real Difference

Sales velocity is how fast a single product sells per day or per week. Sell-through rate measures how efficiently your total inventory position moves relative to what you hold. They answer different questions.

"There's really two things that are important when you are trying to scale your business. The first thing is sales velocity, which means how fast the items that you sell are actually selling. And the second one is days in inventory. It's called inventory age." Chris Mangunza, Try This EASY Sellersnap Repricing Strategy to SCALE Amazon FBA (2025)

You can have great velocity on one ASIN and still have a poor overall sell-through rate because you are holding dead weight on other products. Buy less on slow movers and reprice aggressively on anything already sitting in the warehouse.

Days in inventory is the practical version of sell-through rate at the ASIN level. At 90 days without a sale, that unit is tying up capital and running up storage fees with nothing to show for it.

6. Why Sell-Through Rate Affects Your FBA Capacity Limits

Since March 2023, Amazon replaced restock limits with capacity limits. Each storage type gets its own monthly limit measured in cubic feet. Standard-size, oversize, apparel, and footwear storage each have separate limits.

Amazon sets your capacity limit using several inputs: IPI score, sales forecast, lead time, and available fulfillment center space. Sell-through rate feeds directly into your IPI score. A bad sell-through rate signals to Amazon that you are tying up warehouse space without productive sales output.

The result: tighter capacity limits and less revenue during peak weeks. This is one of the main reasons I review sell-through every week. Find a capacity drop mid-October sourcing run and your whole plan falls apart. See how to improve your IPI score if your limits are already tight, and how to request more capacity through Capacity Manager.

7. Aged Inventory Surcharges: The 181-Day Clock

Amazon's aged inventory surcharges start at 181 days and climb with age. Bad sell-through puts you on that clock. The fees compound fast on slow-moving SKUs.

A unit sitting in an Amazon warehouse for six months is dead capital with a monthly storage fee attached. Cross 181 days and the surcharge kicks in on top of that.

At 120 days, drop the price. If a unit has not moved in four months, you have until 181 days to clear it. After that, you are choosing between paying the surcharge and liquidating below cost. See the full FBA fee breakdown to understand exactly what those surcharge tiers cost per unit.

8. Repricing Is the Fastest Fix for Stuck Inventory

Price is your fastest lever when inventory stalls. Lower it, win the Buy Box, and move units before the aged inventory surcharge hits.

Set up a repricer with floors and ceilings per ASIN. Manual cuts don't hold across a full catalog. The range matters:

"You should get a range for the minimum price and maximum price and a target setting price. The thing you need to know is that the price at which the item is currently selling, if you buy a lead today, whenever your lead is going to check in on Amazon, the price is not going to be the same, especially if you do online arbitrage." Chris Mangunza, Millionaire Seller Unveils Top Amazon FBA Repricing Strategy | Bqool Repricer Masterclass (2024)

Set your minimum price at the floor that still covers fees and leaves acceptable margin. Set your maximum at or near the current Buy Box price. Let the repricer compete within that range automatically. See a full comparison of the top options in the best Amazon repricers for 2026.

9. Sourcing With Sell-Through Rate in Mind

The best time to protect your sell-through rate is before you buy. If you are sourcing a product you expect to turn slowly, either buy fewer units or skip it. Do not let a good price override the data on sales pace.

Keepa's BSR history is the most reliable sell-through predictor available to most sellers. Frequent, sharp BSR drops signal units selling through fast. A flat BSR line means the product barely moves. Before buying any significant quantity, look at six months of BSR data. The Keepa tutorial walks through how to read those graphs accurately.

I also use a simple buy quantity formula: expected daily sales rate times the number of days of inventory I want to hold. If a product sells one unit per day and I want 45 days of supply, I buy 45 units, not 200. Knowing your target sell-through window before buying keeps you out of a slow-inventory hole. See how to figure out exactly how many units to buy for each lead.

10. The Q4 Sell-Through Trap Most Sellers Fall Into

Q4 demand spikes, so sellers buy more. The problem: the spike ends and January arrives before inventory clears. Now you have units approaching the 181-day surcharge threshold as January demand drops off.

For 2026, the FBA arrival deadline for Amazon-optimized splits is October 28. Anything shipping in right now needs to be a product you are confident will sell before Q4 ends. Buy less than you think you need if you are unsure.

Plan for January when you are sourcing in October. Look at BSR trends from January of prior years on the products you are considering. A product with strong Q4 velocity but dead January sales is a sell-through trap waiting to happen. The full Q4 inventory planning guide covers how to structure your buys for this season.

11. Build a Weekly Sell-Through Review Into Your Routine

Sellers who keep their sell-through rate green check it every week and act on what they see. The review takes about 15 minutes once it is a habit.

Every Monday: open FBA Inventory, sort by sell-through rate ascending, and look at everything below 50%. For any ASIN that has been in the warehouse more than 60 days at under 50% sell-through, cut the price that day. Do not wait for it to get worse.

This weekly review is part of the broader system I break down at every live training. Head to /register and grab a free seat for Thursday's session. I source, analyze, and ship a real product live for 60 minutes. You will see exactly how I track sell-through and reprice on the same call.

12. Next Steps

Sell-through rate is one piece of scaling efficiently. Five posts to keep building on:

• The complete guide to scaling your Amazon FBA business
• How to improve your IPI score and get more storage capacity
• Every FBA fee explained, including aged inventory surcharges
• The best Amazon repricers in 2026 compared side by side
• Q4 inventory planning: how to stock the right amount for peak season