How to Remove Tea Stains From Stainless Steel Tumblers

By KINTO Japan | Published: 2026-10-16

Category: Tips & Care

Tea residue builds a brown film inside insulated tumblers. Follow this step-by-step deep clean with baking soda and dish soap to restore a fresh, odor-free interior.

Quick answer

Fill your stainless steel tumbler with warm water, add 1–2 tablespoons of baking soda and a drop of dish soap, then let it sit for 15–30 minutes before scrubbing with a soft bottle brush. Rinse thoroughly and dry upside down. This lifts tea tannins without scratching the interior.

Why tea stains stick to stainless steel

Tea contains tannins that bind to the microscopic pores of stainless steel, leaving a brown film that plain rinsing won't remove. Unlike coffee oils, tannins are water-soluble but need an alkaline boost to release. That's why baking soda works better than soap alone for tea residue.

Insulated tumblers with a narrow mouth are harder to scrub, so stains build up in the corners. If you use your tumbler daily for tea, a weekly deep clean prevents the film from hardening into a stubborn layer.

What you need for a deep clean

Gather warm water, baking soda, mild dish soap, a soft bottle brush, and a microfiber cloth. Avoid steel wool or abrasive cleansers—they scratch the interior and create new places for stains to hide.

For tumblers with a removable lid or straw, take them apart and clean each piece separately. Silicone seals can trap tea residue and cause odors.

Step-by-step cleaning process

Work through the steps below in order. Each step includes a checkpoint so you know when to move on.

How to prevent future tea stains

Rinse your tumbler with hot water immediately after finishing your tea. If you can't wash it right away, fill it with warm water and a pinch of baking soda to soak until you can clean it. Avoid leaving tea sitting overnight, as tannins set faster the longer they contact the steel.

For daily tea drinkers, a weekly baking soda soak keeps stains from accumulating. If you use your tumbler for both tea and coffee, clean it between drinks to avoid flavor transfer.

Cleaning steps

1. Rinse and pre-soak: Empty any leftover tea and rinse with warm water. Fill the tumbler with warm water and add 1 tablespoon of baking soda. Let it sit for 10 minutes to loosen surface stains. Checkpoint: The water should look slightly cloudy as tannins release.
2. Add soap and scrub: Add a drop of mild dish soap to the soaking water. Use a soft bottle brush to scrub the interior walls and bottom, paying attention to the corners where stains collect. Common mistake: Using a harsh brush or steel wool—this scratches the steel and makes stains harder to remove next time.
3. Deep clean stubborn stains: If stains remain, make a paste of baking soda and water. Apply it to the stained areas and let it sit for 15 minutes. Scrub gently with a soft brush, then rinse. Checkpoint: The paste should lift the brown film without scrubbing hard.
4. Clean the lid and straw: Disassemble the lid and straw. Wash them with warm soapy water and a small brush. For silicone seals, use a baking soda paste to remove residue. Common mistake: Forgetting the lid gasket—tea residue there causes odors and leaks.
5. Rinse and dry: Rinse all parts thoroughly with warm water until no soap or baking soda remains. Dry upside down on a rack to let air circulate. Checkpoint: No white film or slippery feel—if present, rinse again.

Product facts

プレイタンブラー 300ml ストロー 2本入り: PLAY TUMBLER 300 ml straw set includes two reusable straws and is made of safe polyethylene. The straws are removable for cleaning, so tea residue doesn't get trapped inside. The lightweight design makes it easy to handle during washing.
プレイタンブラー 300ml/480ml 蓋: Replacement lid fits KINTO PLAY TUMBLER 300ml and 480ml models (part numbers 20361 and 20371). If your lid's seal becomes stained or worn from tea, replacing just the lid restores a clean seal without buying a whole new tumbler.