A compostable trash bag earns its price only when it travels with food scraps to a place that can compost it: a facility that accepts certified bags or, for a few bags, a backyard pile. Buried in a landfill with the rest of the trash, it does no more good than any other bag. So buy for the destination. Scraps going to a city compost cart call for a certified compostable bag in the size and certification the hauler accepts; a backyard pile calls for a bag certified for home composting, or no bag at all; and landfill trash calls for a recycled-plastic bag or one already in the drawer.
Who Gives A Crap covers both ends of that: a 3-gallon compostable food scrap bag for the countertop caddy, and a 100% recycled-plastic bag for the kitchen trash that the company sells for the landfill and does not call compostable. For a tall can that holds nothing but scraps, UNNI and BioBag make 13-gallon compostable bags listed in the Biodegradable Products Institute’s public catalog. A box of ordinary bags already in the house still has a job: finish it in the trash can.
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What Happens to the Bag After Pickup
Food scraps are why the bag question matters at all. EPA estimates that food makes up about 24% of the municipal solid waste landfilled in the United States, and that landfilled food accounts for an estimated 58% of the methane escaping from those landfills, because it decays quickly in a place kept short of air. Moving scraps into a compost cart is the gain. The bag is a carrier that keeps the caddy clean on the way.
A certified compostable bag is made to disappear along with those scraps. Under the Federal Trade Commission’s Green Guides, a company calling a product compostable needs evidence that it turns into usable compost in about the same time as the material it is composted with, in a composting facility or a home pile. The Guides also expect the claim to be qualified when the item can’t be composted at home, when composting facilities aren’t available to a substantial majority of the people it is sold to, and when the label could mislead buyers about what the item does in a landfill.
In a landfill, nothing on the label applies. The Guides treat an unqualified “degradable” claim as deceptive for anything customarily landfilled or incinerated, since neither place lets an item fully decompose within a year, and the example they choose is a trash bag tested in soil and then thrown out with the garbage. That is also why “biodegradable” on a box promises far less than “compostable”: the difference between biodegradable and compostable comes down to conditions, time and proof.
Check Your Hauler Before Buying a Box
City compost programs disagree about bags, sometimes completely. Portland, Oregon, lets residents line a kitchen container with paper or a BPI-certified compostable bag, and sends every other item labeled compostable, biodegradable or made from plants to the trash. Denver takes only small bags approved by the Compost Manufacturing Alliance (CMA), which field-tests products at working compost sites, and the list it posts from its composter, A1 Organics, caps them at 3 gallons and food scraps only. The City of Sonoma, California, accepts no compostable plastics at all, because the facility it uses can’t compost them.
Paper isn’t a universal fallback either: Denver’s guide lists paper products, along with plastics of any kind, among the things that stay out of its green cart. Pet waste is on the same list whatever it is wrapped in, which leaves the choice of a poop bag as a separate question that ends in the trash.
Acceptance doesn’t guarantee a bag becomes compost. When CalRecycle surveyed California’s permitted mixed-material composting facilities in 2023, none of the 24 that answered said it worked plastic products into finished compost, and most did not take plastic products at all. A1 Organics explains its CMA rule the same way: bags certified under lab conditions can fail to break down fast enough in its process, and those end up as contamination in the compost or are sent to a landfill.
So the hauler’s own page settles the purchase. It will say whether bags are allowed, which certification it accepts and whether size is limited, and a program that takes only 3-gallon bags makes a box of 13-gallon bags useless, however well certified.
What a Compostable Bag’s Box Should Show
California spells out what these bags must show, and its rules make a useful checklist anywhere. According to CalRecycle, a compostable plastic bag sold in the state must carry a certification logo showing it meets ASTM D6400, the U.S. compostability standard for plastics, and must not display a chasing-arrows or resin-code symbol. It must also be uniformly green with “compostable” printed at least an inch high, or carry “compostable” on both sides in inch-high green letters or on a green band. A product labeled “home compostable” there must meet the OK compost HOME certification requirements, and the state restricts marketing with terms like “biodegradable.”
A certification can be looked up by name. BPI’s public catalog lists certified products by brand and item: UNNI’s 13-gallon bags appear under UNNI Corporation, and BioBag’s tall 13-gallon food waste bag appears under BioBag Americas as item 187684.
Compostable Bags for the Compost Cart
The three compostable bags differ most in size and price per bag. The recycled bag in the last row belongs in the trash can, where none of the compostable ones should go.
| Bag (price, Nov 2026) | Size and count | Thickness | Certifications the maker lists | Where it belongs | Buy |
|---|---|---|---|---|---|
|
Who Gives A Crap Compostable Food Scrap Bags $19 for 60, about 32¢ a bag; sold out in November 2026 |
3 gallons; two rolls of 30 | Not disclosed | BPI (ASTM D6400); OK compost HOME | Countertop caddy for the compost cart | — |
|
UNNI Compostable Bags, 13 Gallon $67.98 for 200 at Amazon, about 34¢ a bag |
13 gallons, 23.75 × 31.49 in; four rolls of 50 | 0.9 mil | BPI (ASTM D6400); CMA; OK compost HOME | Tall can of food scraps | Buy at Amazon |
|
BioBag Tall Kitchen Compostable Bags, 13 Gallon $25.99 for 48 at Amazon, about 54¢ a bag |
13 gallons, 22.2 × 29 in | 0.68 mil | BPI (ASTM D6400); CMA; OK compost INDUSTRIAL and HOME | Tall can of food scraps | Buy at Amazon |
|
Who Gives A Crap 100% Recycled Trash Bags $18 for 40 tall, about 45¢ a bag; $13 for 60 small |
13 gallons, 24 × 39.8 in; or 4 gallons, 18.1 × 25.6 in | Not disclosed | None; not compostable | Landfill trash | Buy at Who Gives A Crap |
Who Gives A Crap Compostable Food Scrap Bags
Who Gives A Crap’s food scrap bags are sized for a countertop caddy: 3 gallons, 60 bags on two rolls, with tie handles, for $19, about 32 cents a bag; the company listed them as sold out in November 2026. The company says they are made with plant matter, without naming the resin, and that they are BPI certified for industrial composting to ASTM D6400 and carry TÜV Austria’s OK compost HOME mark, though not a U.S. home-composting certification.
The bags start to break down once they are damp and warm, so the company suggests a fresh bag about every three days, which it says also keeps the bin fresh and dry; the countertop compost bin guide reaches the same conclusion, that emptying often controls smell more than the bin does. Who Gives A Crap puts breakdown at about three months in an industrial facility and about 12 months in a home pile, and its own FAQ asks buyers not to use these bags for landfill trash. The carton is recyclable.
Tall 13-Gallon Bags From UNNI and BioBag
A tall can lined with a 13-gallon compostable bag suits a household that collects scraps in one big bin and empties it into the cart every few days. UNNI’s bag is the thicker of the two, at 0.9 mil and 23.75 by 31.49 inches; Amazon listed the 200-count box, four rolls of 50, at $67.98 in November 2026, sold by UNNI, or about 34 cents a bag. UNNI lists BPI certification to ASTM D6400, CMA approval and TÜV Austria’s OK compost HOME, and says to use the bags within nine months, stored somewhere cool and dry.
BioBag’s tall kitchen bag is thinner, 0.68 mil and 22.2 by 29 inches, and costs more per bag: $25.99 for 48 at Amazon, sold by Amazon, in November 2026, about 54 cents each. BioBag, part of the Novamont group, makes it in the U.S. from Mater-Bi resin sourced in Italy, which it describes as starch and vegetable-oil derivatives combined with compostable polymers, and lists BPI and CMA certification plus TÜV Austria’s OK compost INDUSTRIAL and HOME marks.
Where a program takes any BPI-certified bag, UNNI’s is the thicker bag and the cheaper one per use. Neither fits under Denver’s 3-gallon limit, and a household that empties a small caddy daily needs neither.
A Backyard Pile Needs a Home-Certified Bag, or None
A home pile runs cooler than an industrial composting facility, which TÜV Austria, the certifier behind the OK compost marks, puts at 55 to 60°C. TÜV says products certified only as OK compost INDUSTRIAL should not go into garden compost, while OK compost HOME products also compost at lower temperatures. All three compostable bags above carry the HOME mark by their makers’ accounts. BPI’s catalog has a column for its own home certification, and in November 2026 it was empty for the UNNI and BioBag bags; Who Gives A Crap says its bags have no U.S. home certification.
A bag is optional in a backyard system anyway. Scraps can go from a lidded caddy straight onto the pile, where the balance of food scraps and dry browns matters more than what carried them out, and the home composting guide covers that balance.
For the Trash Can: Recycled Plastic, or a Bag You Already Have
Once food scraps go to compost, what is left in the kitchen trash is drier and headed for a landfill or an incinerator whatever its bag says, so a compostable bag adds cost and nothing else. The lowest-waste liner is one already in the house: bread bags, produce bags, cereal liners and mailers hold a small can’s worth, and a small can of dry trash can go unlined with a rinse now and then. A box of ordinary trash bags still has a job after the switch to composting. Use it up in the trash can and never in the compost cart; Denver’s guide puts it plainly, telling residents never to put compost in plastic bags.
Who Gives A Crap 100% Recycled Trash Bags
When a new box is needed, Who Gives A Crap’s recycled bags are the ones built for this can. The Tall Kitchen size holds 13 gallons, measures 24 by 39.8 inches and comes 40 to a pack on two rolls for $18 (Nov 2026), about 45 cents a bag; the Small 4-gallon size is 60 bags on three rolls for $13. The company says they are made from 100% recycled plastic, without saying how much of it was post-consumer, and that they are not biodegradable.
They tie with built-in handles instead of drawstrings, which the company says can’t be made from recycled plastic. Its case against “biodegradable” bags rests on landfill methane: a bag that doesn’t break down anaerobically, it argues, releases little methane there. That is the company’s argument; the plainer point is that a recycled bag is made from plastic that already exists instead of new resin.
Using Up What You Have, and Where Each Bag Ends Up
Compostable bags don’t keep forever. UNNI says to use its bags within nine months, and Who Gives A Crap says its bags begin breaking down with moisture and heat, so a bulk box bought to save money can weaken in a warm cupboard before the last roll is used. Buy the count a few months of scraps will need. If a box turns out not to suit the local program, using the bags as ordinary trash liners wastes less than throwing them away unused.
At the end, a compostable bag goes into the compost cart with the scraps, or into a home pile if it carries a home mark. With neither available, it goes in the trash; California forbids chasing-arrows symbols on these bags, so nothing on a legitimate box should send it to the recycling bin. A recycled-plastic bag goes out with the garbage it holds. Both Who Gives A Crap products ship in cartons the company calls recyclable. The cleanest outcome belongs to a caddy emptied loose into a cart that takes scraps without a bag: A1 Organics, whose bag list Denver posts, calls skipping the liner the most sustainable option.
Sources
- EPA: Quantifying Methane Emissions from Landfilled Food Waste
- FTC Green Guides, 16 CFR 260.7: Compostable claims
- FTC Green Guides, 16 CFR 260.8: Degradable claims
- CalRecycle: Truth-in-Labeling Laws (compostable and degradable products)
- CalRecycle: AB 1201 bifurcated collection determination and composter survey (Dec 2023)
- City of Portland: Compost tips
- City and County of Denver: Compost service guide
- A1 Organics: Acceptable CMA-approved compostable bags (posted by Denver)
- City of Sonoma: Bio-plastics and compostable plastics in the compost cart
- TÜV Austria: OK compost HOME
- Biodegradable Products Institute: certified product catalog
- UNNI: 13 Gallon Compostable Tall Kitchen Food Scrap Bag
- BioBag: Tall Kitchen 13 Gallon Food Scrap Bags