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FOAMON

Replacement Seat for Herman Miller Classic Aeron Size B Medium (Black Mesh)

Based on 253 reviews
Condition: New
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$159.94
Holiday Deal · 6% off was $169.99

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This item's return window has been extended for the holiday season: FREE refund/replacement until Jan 31, 2027

To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.

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Availability: In Stock.
Fulfilled by Amazon
Arrives Dec 13 – Dec 28
Order within 3 hours and 47 minutes

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At a glance

Condition
New
Color
Graphite
Model
B3D01
Dimensions
18 x 20.25 x 6 in
Weight
4.6 lb
Material
Plastic
Size
Medium
In the box
Seat

Features 5

  • Fits Classic Aeron Size B Only: Made for the Herman Miller Classic Aeron (1994-2016) in Size B, Medium. It does not fit Size A or Size C, the Aeron Remastered (2016 and later), or other Herman Miller chairs such as the Mirra.
  • Check Your Size First: Look under the top edge of your backrest. Two dots means Size B, and this seat fits. Three dots means Size C, which uses a larger seat pan, so this seat will not line up. Please check before ordering.
  • Complete Seat, Ready to Install: Arrives fully assembled with a graphite frame and tensioned black suspension mesh. It replaces a sagging, torn or worn seat, so you can keep the Aeron you already own instead of buying a new chair.
  • Exact Size B Dimensions: Measures about 20.25 inches wide, 18 inches deep and 5.8 inches high to match the original Classic Aeron Size B seat, and keeps the original graphite and black look.

Specs 45

Brand FOAMON
Color Graphite
Material Plastic
Product Dimensions 18"D x 20.2"W x 5.8"H
Size Medium
Brand Name FOAMON
Additional Features Breathable
Unit Count 1 Count

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Dec 13 – Dec 28

Yes, absolutely! This item's return window has been extended for the holiday season: FREE refund/replacement until Jan 31, 2027.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

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Top Amazon Reviews

Perfect seat replacement for my size B Aeron chair
Color: Graphite
I have an Aeron chair (size B) that I bought in the late 90s. A few years ago the seat started to tear. Not bad after 20+ years of almost daily use. I bought a replacement mesh which turned out to be a bad idea. It didn't quite fit and it wasn't made of the same stretch material as the original seat. Ok, lesson learned there. So I bought this and it was a perfect replacement. It's an entire new seat, not just the mesh. The mesh is the same stretchy material as the original. It looks identical to the original seat as far as I can tell. Replacing the seat was pretty easy. The instructions were good and it came with the tools needed. I think it took about 20 minutes and I was done. If you've made an investment in this chair, I think it's worth it to spend a little more getting this replacement seat so you have the official product. I'm writing this review 2.5 years later in Feb 2026 and the seat is still great. Zero problems, no regrets. ... show more
Reviewed in the United States on February 4, 2026 by Matt
very nice
Color: Graphite
It came on time and had the tools with it. it fit perfectly with very minimal adjustment. it has been used daily for the last year without any issues.
Reviewed in the United States on August 21, 2026 by bg
Glad I bought it
Color: Graphite
When the seat of my 30+ year old Aeron chair failed, I started looking for replacement chairs, and then read a Consumer Report review of office chairs. It still had the Aeron chair listed as one of their top choices. This encouraged me to look to repair rather than replace the chair, and I came upon this replacement seat. After watching several YouTube videos, I started the replacement process. For the most part, the process went smoothly. Getting the seat and the swing arms detached was relatively easy. Getting the replacement seat and one of the swing arms reattached was also relatively easy. Getting the second swing arm reattached was a bit of a challenge. I own what may be a first-generation Aeron chair, and as shown in the instructions, there are bushings and a spacer that were replaced on more modern versions of the chair. Dealing with the bushings and the spacer on this second arm was a bit of a chore. Add in that I am in my 70s, and don't have a good work bench to work on. Some choice words were uttered while trying to get the hole, bushing, and screw into alignment on that final connection. That said, I dd get it back together, and it seems to function just as it did before the tearing. I do wonder whether over time there has been some distortion/warping of the seat that made reattaching the second swing arm more difficult. In the end, it was worth the effort. I will note that my seat frame was intact, and it was only after i ordered that i noticed one could buy just the mesh insert and replace it. If I live long enough to need to replace the mesh again, this might be the route I pursue. It reduces the cost to about half of what this product runs. For now I am happy to have my chair back. ... show more
Reviewed in the United States on June 9, 2024 by A. M. Glaeser
Flat, not curved like the official seats
Color: Graphite
DO NOT BUY! This seat cushion does not have the same curve as a classic herman miller seat. It's hard to show in an image, but the official seats curve upwards from the back, with a high point at the center. This seat is completely flat, giving you far less support. It looks correct, and feels correct when you first sit, but over time it becomes clear that this is NOT a valid replacement. ... show more
Reviewed in the United States on August 31, 2026 by Jason
Good enough to buy twice
Color: Graphite
I bought this replacement seat pan in June 2022, which made my chair feel like new again. By May 2026, I felt like I was sagging into the middle. I decided to buy the part again, as four years seems acceptable (if not great) for longevity: even Crandall only warrantees its seat pan for two years. During that time, my weight averaged about 180 lbs. Placing the two seat pans side by side on the floor, the difference was obvious. When I pushed down at the middle of the old one's pellicle, my hand reached the floor. When I pushed down in the middle of the new one, it came nowhere close. Installation, as other people have noted, is very easy. ... show more
Reviewed in the United States on May 25, 2026 by D B B
Great replacement
Color: Graphite
The seat was a good replacement and fit exactly like the old one that broke on my chair. It came with the seat and the tools to replace it. Easy to install and it feels like a new chair, now I can keep using my chair.
Reviewed in the United States on June 29, 2026 by Amazon Customer
Strong chemical smell, not exact match mesh, great value if you can overcome those issues
Color: Graphite
The mesh looks different from original. My after market headrest made by Atlas Headrest is an exact match to the original mesh. The color here is darker and the fiber bands are thinner in this material. The mesh plastic was not flush to the tray, and sunken in the back quite a bit, which is visible in another reviewers photo. I could have lived with all those things because the mesh felt tight and the tools and packaging are impressive, but the product has an overwhelming chemical smell that is quite offensive to my nose and eyes. The plastic in the tray is lighter and softer than the original, having less glass-fill in the plastic. This product is a fantastic option, but did not live up to my standards. ... show more
Reviewed in the United States on April 28, 2025 by Carmelo Estrada
OEM Level Quality!
Color: Graphite
OEM level quality for less & all tools included to complete the replacement. Note: if you need new side pivot bolts, they are separate!
Reviewed in the United States on August 16, 2026 by James Ruggiero
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