Comparing the main routes for bio-based fibers on cost, fit and follow-through

What to take away

The three routes, by name

Bio-based fiber sourcing splits into three routes. Each route has named commercial examples a buyer can request today.

Natural fibers are separated from plants or animals: cotton, flax, hemp, and wool. Upland cotton remains the volume leader. Organic cotton carries a chain-of-custody certificate under GOTS.

Manufactured cellulosics dissolve and regenerate cellulose. Named fibers include viscose, modal, and lyocell, sold by Lenzing as Tencel and by Birla as Birla Cellulose. Eastman makes Naia from wood pulp. Renewcell turned post-consumer cotton into Circulose pulp before its 2024 insolvency, a lesson in follow-through.

Biosynthetics polymerize biological feedstocks. Named materials include PLA from NatureWorks, bio-PET from plant-derived monoethylene glycol, and PHA from Danimer Scientific and Kaneka. Bolt Threads makes Mylo from mycelium. Spiber makes Brewed Protein from fermented sugars.

Route-level definitions sit in the bio-based fibers primer. The biofabricated material comparison covers grown and fermented routes in more detail.

Cost: typical bands and the drivers behind them

No public list price covers most of these fibers, so read the bands below as typical ranges rather than quotes. Quotes move with volume, contract length, and region. What you can compare is the cost structure.

Typical bands, as of 2026: conventional cotton lint at $1.50 to $2.60 per kilogram, organic cotton at a 10% to 30% premium over conventional, and hemp bast fiber at $2.00 to $4.00.

Viscose runs $1.60 to $2.40 per kilogram, and lyocell runs $3.00 to $4.50, because solvent recovery costs more than the viscose process it replaces. PLA runs $1.80 to $2.60 against conventional PET, so oil prices move it.

Bio-PET tracks PET resin at roughly $1.30 to $1.90 per kilogram. PHA runs $3.00 to $6.00, because fermentation capacity is small and extraction yields vary by strain.

For your own arithmetic, build the number from named variables:

Multiply and add. The current published figure for any of these belongs in your supplier quote, not in a general article.

Import duties on these fibers vary by HTS code, origin, and trade program. Confirm the rate with US Customs and Border Protection or a licensed customs broker before you commit to a landed cost.

Fit: matching fiber to garment

Fit means whether the fiber performs in the garment you are making, in the climate where it will be worn.

A hemp tee works in Portland. A hemp swimsuit does not, because hemp absorbs water and loses shape when wet.

A lyocell summer dress drapes well and wrinkles. A PLA shirt softens at temperatures a hot iron reaches, so care instructions become a design constraint.

Bio-PET behaves like PET. That is why it fits activewear, and why it does not biodegrade.

Test the finished fabric, not the fiber. The checks that separate a good match from a bad one:

A fiber that passes the swatch test can still fail the wear trial. Run both. Garment-by-garment behavior for natural fibers is covered in the natural fiber comparison by garment use.

Follow-through: what happens after the sale

Follow-through has three parts: the claim survives scrutiny, the material traces to the lot, and an end route exists for the used garment.

On claims, the FTC Green Guides set the standard for what "bio-based," "biodegradable," and "compostable" may mean in US marketing. Qualified counsel reviews final claim language. This article does not.

On traceability, ask for the pulp origin, the bio-based share with its test method, the facility data, and the lot number. A supplier who cannot produce these for the exact batch is selling route-level information, not product-level detail.

On end routes, origin does not determine disposal. An Eionet technical report on plastics in textiles and circularity separates bio-based origin from biodegradability. Bio-PET is generally not biodegradable. PLA biodegrades only under industrial composting conditions, and only if a collector in your market accepts it.

WIPO's review of raw-material extraction and textile manufacture describes agricultural-waste feedstocks. It notes that a biological input can score worse in some impact categories than the fossil route it replaces. Route names do not settle impact.

Worked example: a 5,000-unit summer shirt

A brand is choosing between organic cotton poplin and lyocell poplin for a 5,000-unit summer shirt run.

Cost side: fiber price per kilogram multiplied by grams per shirt, plus cutting waste, duty, and the certification fee per shipment.

Organic cotton carries a certification fee and a bale-level MOQ. Lyocell carries a higher fiber price and a mill-level tonne MOQ. At 5,000 units the mill minimum may decide the question, not the fiber price.

Fit side: both drape and breathe. Cotton holds shape after washing; lyocell may need lower iron temperatures and shrinks differently. Run the wash trial on both before committing.

Follow-through side: cotton has established resale and recycling channels. Lyocell has fewer collectors, though the fiber re-dissolves in principle. Check whether a collector in your market takes the finished shirt with its buttons and thread.

The decision rule: reject any option that fails a mandatory performance or care test, then compare the evidence quality on feedstock, processing, expected life, and end route.

When two options are close, pick the one likely to be worn more, repaired more easily, and cared for within the owner's routine.

The general comparison method applies the same logic beyond materials.

Common questions

Which route is cheapest per kilogram?

Typical bands put conventional cotton lint at $1.50 to $2.60 per kilogram and viscose at $1.60 to $2.40. Lyocell runs $3.00 to $4.50, and PHA runs $3.00 to $6.00. Organic cotton carries a certification premium over conventional. Get current quotes from your supplier, because published ranges age quickly.

Are manufactured cellulosics synthetic?

They are a separate manufactured-fiber group. The cellulose comes from wood pulp or cotton linters, then is dissolved and regenerated, so the input is natural and the process is industrial. State the route rather than relying on one label.

Is a 100 percent bio-based polymer better than a partly bio-based one?

The percentage answers only the feedstock question. Bio-PET is often partly bio-based and performs like PET. Performance, land use, processing energy, product life, and disposal still need separate comparison.

Should blends always be avoided?

No. A small elastane percentage can add recovery that a pure fiber cannot. Judge whether the added material delivers a needed property, then record the effect on repair and on fiber-to-fiber recycling.