Plastic-Free Tea Bags UK (2026): Which Brands Really Are, and What PLA Means

Which tea bags are plastic-free in the UK?

Fewer than most people think. According to a Which? investigation published in October 2025, most UK tea bags, including Yorkshire Tea, PG tips Original, Tetley black tea, Typhoo, Twinings everyday bags, Teapigs and nearly every supermarket own brand, are sealed or made with PLA (polylactic acid), a plastic made from plants. The bags Which? lists as genuinely plastic-free are Hampstead, Pukka, and the string and tag ranges from Clipper, Twinings and Dragonfly.

The lowest-exposure option of all is loose leaf tea brewed in a teapot or stainless steel infuser, because there is no bag to shed anything.

Our picks at a glance

How we chose

We started from the most recent independent brand survey, the Which? October 2025 table, then checked brand statements and current UK prices at brand sites and Ocado. We ranked loose leaf highest because it removes the bag entirely, then bags that avoid both polypropylene and PLA. No study has measured particle release from these exact products, so the best grade we give is moderate: the material evidence is clear, product-level testing is missing.

Do tea bags really release microplastics?

Some do, and in large numbers. In a 2019 McGill University study in Environmental Science & Technology, steeping a single plastic mesh tea bag (nylon or PET, the silky pyramid type) at 95°C released about 11.6 billion microplastics and 3.1 billion nanoplastics into one cup. Those numbers are for fully plastic mesh bags, not paper bags with a plastic seal, and the counting methods have been debated.

A 2024 study from the Universitat Autonoma de Barcelona in Chemosphere tested nylon-6, polypropylene and cellulose bags. All three released particles into the water, and human intestinal cells took them up in the lab. A 2025 review in Food Chemistry concluded that tea bags are the main source of micro and nanoplastics in tea, and that composite and "biodegradable" bags also release significant quantities, though results vary between labs because methods differ.

What we do not know is what these particles do in people at realistic doses. Lab cell studies show particles can be absorbed, but there is no human evidence of harm from tea specifically. This is a reasonable place to lower exposure because the swap is cheap and easy, not because harm has been proven.

Is PLA plastic? What "plant-based" tea bags really mean

Yes. PLA is a bioplastic usually made from corn starch or sugarcane. It replaced oil-based polypropylene as the heat seal in many brands from 2018 onwards:

• Yorkshire Tea says its bags now use "a plant-based plastic called polylactic acid, or PLA" instead of polypropylene.
• Clipper's heat-seal bags are a blend of abaca, plant cellulose and non-GM PLA, according to its 2018 launch announcement, even though the boxes say "plastic-free".
• PG tips switched to a corn starch based material in 2018.
• Teapigs tea temples are cornstarch mesh, which is PLA.

Which? says calling PLA bags "plastic-free" or "microplastic-free" is misleading, because PLA is still a plastic and can shed particles. PLA also only breaks down in industrial composting, not in a home compost heap. It is a better end-of-life story than polypropylene, but not a lower-exposure one by default.

Our picks

Brew Tea Co English Breakfast Loose Leaf: best overall

Loose leaf removes the bag, which is where the particle research points. Brew Tea Co's English Breakfast is whole rolled leaf with no dust, and it makes a strong, malty cup in a pot or steel infuser.

Honest caveat: Which? lists Brew's tea bags as PLA, so buy the loose leaf, not the bags. Use a stainless steel infuser, not a plastic or nylon one.

Yorkshire Tea Loose Leaf 250g: best budget

If you love Yorkshire Tea, its loose leaf gives you the same taste without the PLA bag, for about £3.45 at Ocado.

Honest caveat: you need a teapot or infuser and a minute more. Yorkshire Tea's own bags are PLA.

Hampstead Organic English Breakfast Tea Bags: best plastic-free bag

Which? lists Hampstead bags as plastic-free and certified home compostable, and the brand says it uses no PLA glue. It is the easiest swap for black tea drinkers who want a bag.

Honest caveat: Which? notes the envelopes on Hampstead's Earl Grey and Green Tea and Jasmine contain a thin plastic layer. No one has tested these bags for particle release.

Pukka Organic Herbal Collection: best herbal

Pukka's bags are stitched with organic cotton rather than heat-sealed, and Which? lists them as plastic-free and home compostable. The herbal collection is stocked widely.

Honest caveat: each bag sits in an envelope that, according to Which?, contains a very small amount of plastic. Check herbal ingredients if you are pregnant or take medication.

Twinings Peppermint (string and tag): cheap herbal option

Which? lists Twinings string and tag bags as plastic-free, while its everyday heat-sealed bags use PLA. The 20-bag peppermint is one of the cheapest herbal teas in a plastic-free format.

Honest caveat: check the box says "string and tag"; the retailer page does not state the bag material.

Teapigs tea temples: what PLA mesh means

We include Teapigs because its pyramids look like the nylon bags in the 2019 study but are not the same thing. They are cornstarch PLA, not nylon or PET.

Honest caveat: PLA is still plastic, needs industrial composting, and Which? classes Teapigs as PLA. Its loose leaf range avoids the mesh altogether.

What to avoid

• Silky nylon or PET pyramid bags, the type tested in the McGill study. Some premium and supermarket ranges still use them.
• Assuming "plant-based" or "biodegradable" means plastic-free. It usually means PLA.
• Plastic or nylon infusers and cold brew bottles for hot tea. Use stainless steel, glass or a ceramic teapot.
• Squeezing or stirring bags hard if you do use them; it may increase what comes off the bag, though this has not been measured precisely.

How do I switch to loose leaf without the hassle?

Use about one teaspoon (2 to 3g) per cup in a teapot or a large stainless steel infuser basket that sits in your mug. Brew black tea for three to five minutes, then lift the basket out. Empty leaves straight into the food waste caddy or garden compost. A 250g pack makes roughly 100 cups, so loose leaf is often cheaper per cup than branded bags.

Bottom line

The simplest way to avoid plastic in tea is loose leaf, such as Brew Tea Co or Yorkshire Tea Loose Leaf. If you prefer bags, choose brands Which? confirms are plastic-free: Hampstead for black tea, Pukka for herbal, or string and tag bags from Twinings and Clipper. Treat "plant-based" bags as PLA plastic, and skip silky nylon pyramids.