10 Best Office Chair Adjustable Seat Depth 2025 in the United States

The Ergalithic Ergonomic Office Chair offers solid ergonomic support with adjustable lumbar support, a breathable mesh seat, and a reclining backrest that adjusts between 90° and 120°. It supports up to 330 pounds, making it generally sturdy and suitable for most adults between 5'5" and 6'2". The seat depth is about 20.1 inches, which is spacious and comfortable for a variety of users. The chair's mechanism allows easy adjustments for height, backrest tilt, and arm positions, contributing to its ergonomic design and comfort for long hours of sitting.

Users appreciate the smooth 360° swivel and quiet rolling wheels, ideal for office or gaming setups on hard floors. Assembly is straightforward, with all tools included and clear instructions. With a 4.4 out of 5 stars from 460 reviews, most users find it comfortable and supportive, though some may wish for more advanced seat depth customization or additional padding in the cushion. The mesh material keeps you cool but might feel less plush compared to fully padded chairs.

This chair suits those looking for a versatile, ergonomic office or gaming chair with good lumbar support and decent adjustability, especially if extensive seat depth adjustments are not a priority.

The Steelcase Amia Office Chair is designed to offer a comfortable and supportive sitting experience, especially suited for office use where you might be seated for many hours. One of its strong points is the ergonomic design, featuring a LiveLumbar system that automatically adjusts to your movements to provide continuous lower back support. The chair’s seat is well-cushioned with foam and has flexible edges to reduce pressure, which is great if you spend long periods sitting.

The seat depth is fixed at 18.5 inches, so it doesn't offer an adjustable seat depth range, which might be a downside if you need to customize that specifically for your leg length. However, it does provide several other useful adjustments, including 4D armrests that move in multiple directions and a reclining mechanism that can lock in place. Users generally rate the chair around 4 out of 5 stars, appreciating its comfort and build quality, though some note it can feel a bit firm initially and the price is on the higher side.

The chair supports up to 400 pounds and has a sturdy build, making it a durable choice. Its fabric upholstery and modern look suit most office settings, and it’s also a carbon-neutral product, reflecting an environmentally friendly approach. If adjustable seat depth is a must for you, this chair may fall short, but for a reliable ergonomic office chair with solid lumbar support and multiple armrest adjustments, the Amia is a strong contender.

The Herman Miller Office Chair (Size B) offers a range of adjustable features designed to increase comfort and ergonomics in an office setting. One of its standout features is the adjustable seat depth, which can be crucial for achieving proper posture and reducing strain during long hours of sitting. The chair also includes height-adjustable arms with pivoting rotation, which allows users to customize the armrest position according to their needs.

The rear and forward tilt limiter adds to the ergonomic design, providing flexibility in how you sit and lean back, further enhancing comfort. The inclusion of an adjustable lumbar pad ensures additional support for the lower back, which is a common area of discomfort for many office workers. The 10-year warranty is highly reassuring, indicating that the chair is built to last and that the company stands behind its product.

The roller blade style hardwood floor wheels are a nice touch, making it easy to move around without damaging floors. However, the chair does come with a few potential drawbacks. It is often on the higher end of the price spectrum, which might not be suitable for all budgets. Additionally, while the chair is 'renewed' to feel brand new, some users might prefer a completely new product over a refurbished one. The solid back design, while supportive, may not be as breathable as mesh options, which could be a consideration for users in warmer environments. This chair would be an excellent choice for someone who spends a lot of time at their desk and is looking for a high-quality, adjustable, and ergonomic seating solution.