In this article:

• Why use BYO coffee cups?
• Product profiles: price, capacity, heat retention, design and ease-of-use
• How we test
• Reusable cups comparison table
• Making sure your BYO cup makes a difference

Saving the environment, one coffee at a time

It's now well-recognised that disposable coffee cups are largely unrecyclable and an environmental disaster across the world, filling up landfill and polluting waterways and our environs. So waste-conscious Australians are taking responsibility into their own hands for their take-away caffeine indulgence by investing in reusable BYO coffee cups (#byocup).

Where once these were large insulated vessels that could accommodate half a pint or more of coffee, probably poured from a drip filter coffee pot and drunk over four or more hours, there's now a wide range of sizes and styles to fit the full menu of coffees on offer in Australia's thriving cafe culture. 

And if you have a cafe in your 'hood that's signed up to responsiblecafes.org, bringing your own cup could save you around 50c on your coffee.

Whether you're using it on your commute, at your desk or on the weekend there's likely to be a perfect mobile mug out there for you. Which one you prefer when it comes to look and feel can be subjective, but if you're after a cup that keeps drinks hotter for longer, our test found that the double-walled products retained the most heat, and of those, the stainless steel models performed better than plastic and ceramic. See our product profiles below for heat retention scores, user trial scores and a breakdown of good and bad points for each cup.

Product profiles

The products are listed below in order of how they rated in our user trial, from highest to lowest score. The recommended retail price (RRP) and cup capacity stated in the profile is for the cup size we tested. Ounces (oz) are displayed where the manufacturer uses ounces on its website, but we've also included the measurement in mL for easier comparison. Some cups come in a range of sizes, and this information is provided in the reusable cups comparison table.

KeepCup Original

RRP: $16 (340mL/12oz)

Heat retention score: 52%

User trial score: 8/10

Plastics and silicone

Good points

• Highest user trial score
• Popular design, wide colour range
• All parts are replaceable
• Easy to carry
• Hard to break, durable
• Sealable lid
• Cover over the drinking hole protects it from dirty handling

Bad points

• Stiff lid can be hard to remove

Klean Kanteen Insulated Tumbler

RRP: $40.50 (473mL)

Heat retention score: 89%

User trial score: 7.2/10

Double wall stainless steel with plastic lid

Good points

• Excellent heat retention, best we tested
• Good for large hot drinks (smaller sizes also available)
• Popular tapered design, with a stable heavy base
• Tumbler lid is replaceable if the seal becomes worn
• Hard-wearing steel

Bad points

• Not sealable
• Triallists found the 473mL cup quite big to handle
• 473mL size was too tall to fit under the cafe's coffee machine group head
• The most expensive cup trialled
• Handwashing recommended

KeepCup Brew

RRP: $26 (340mL/12oz)

Heat retention score: 51%

User trial score: 6.4/10

Tempered glass, plastic, silicone

Good points

• Popular customisable colours
• All parts are replaceable
• Easy-to-carry style with silicone grip
• Triallists liked drinking from the cup with or without the lid  
• Glass does not retain odours
• Cover over the drinking hole protects it from dirty handling

Bad points

• Lowest heat retention of the nine tested cups – this is not the cup for those who like to take their time over a hot coffee
• Silicone strip too narrow as glass can be too hot to touch
• Glass needs to be handled with care
• Stiff lid that can be hard to remove

Avanti Go Mug

RRP: $12.95 (250mL)

Heat retention score: 54%

User trial score: 6/10

Porcelain and silicone

Good points

• Variety of patterns available
• Easy to clean
• Porcelain does not retain odours
• Pleasant to sip from the cup or the lid

Bad points

• Lid is flexible and easy to remove, but considered flimsy
• The heaviest of the cups trialled
• Porcelain needs to be handled with care, no silicone band
• Opening not sealable

Cheeki Coffee Mug

RRP: $34.95 (350mL)

Heat retention score: 87%

User trial score: 5.8/10

Double-walled vacuum insulated stainless steel, plastic

Good points

• Very good heat retention, while the outside stays cool
• Replacement lids available
• Sealable pop-up lid
• Can drink from all sides – a bonus when driving
• Hard-wearing steel

Bad points

• Narrow base fits in cup holders but could compromise stability
• The lid can hold some residue after being closed causing drips, and is hard to clean. Only the lid is dishwasher safe
• Too tall to fit under the cafe's coffee machine group head. Triallists found both lid and cup hard to grip

Frank Green Smart Cup

RRP: $34.95 (340mL/12oz)

Heat retention score: 54%

User trial score: 5.6/10

Plastic

Good points

• Popular design and colours
• Replacement lids and bases available
• Very light, comfortable and slender size cup to carry around, with a good grippy surface
• If the lid is screwed on tightly it seals and won't leak, so it can go in a bag after use
• Fits a bike bottle-holder
• CafePay-enabled for cashless and cardless caffeine

Bad points

• Lid isn't microwave safe
• Harder to clean the lid, and the outside grip attracts dirt
• The rim isn't comfortable to drink from without the lid
• Drinking hole isn't protected from contamination from handling
• The button to open the lid is stiff

Bodum Travel Mug

RRP: $25 (350mL)

Heat retention score: 59%

User trial score: 5.2/10

Double walled plastic and silicone

Good points

• Lightweight, very grippy, 4/5 triallists liked the feel of it
• Screw-on lid and good seal

Bad points

• Too tall to fit under the cafe's coffee machine group head
• Large and plastic, bulky
• You cannot sip from the cup lip, only through the spout

Joco Coffee Cup

RRP: $26.95 (340mL/12oz)

Heat retention score: 52%

User trial score: 5.2/10

Glass, silicone

Good points

• Popular design with triallists, wide colour range
• Replacement lids, cups and bands available
• Glass does not retain odours
• Flexible lid is easy to put on but didn't feel secure
• Glass rim was good to drink from

Bad points

• Glass gets very hot, but large silicone grip helped
• Drink opening doesn't seal ("not the best when running to catch the train")
• Glass needs to be handled with care

Thermocafe Travel Mug by Thermos

RRP: $17 (450mL)

Heat retention score:  68%

User trial score: 2.6/10

Double-walled stainless steel, plastic

Good points

• Hard-wearing steel
• Lid is easily detached and attached; has a seal that isn't waterproof but will stop drips and splashing
• Easy to clean

Bad points

• Too tall to fit under the cafe's coffee machine group head
• Very large and bulky
• Top heavy design means it could be knocked over easily
• Triallists considered it ugly
• Handwash only

How we test

_{Thermal testing the cups in our lab}

User trial. Five people were recruited to each trial nine different reusable coffee cups. For each cup, triallists drank at least two coffees in it over a day, at least one of which was bought from a cafe. Triallists cleaned the cup after each use, and completed a survey form for the cup at the end of the day of use, which included giving each cup an overall rating out of 10. User score is the average of these ratings.

Thermal test. Cups were filled with boiling water and temperature loss was measured using thermocouples inserted through the centre of each cup's lid, and logged over a 12-hour period. The ambient temperature of the test lab ranged from 19.9°C to 20.6°C over this period. The heat retention score calculation was based on the amount of time it took for the liquid to go from hot (85°C) to lukewarm (40°C). The higher the score, the longer the cup keeps your beverage warm. 

Reusable cup comparison table

We compared nine BYO coffee cups, listed below in alphabetical order. To order by another criteria, simply click on the column headings.

Brand/product	Cup image	User score (out of 10)*	Heat retention score (%)*	Time from 85°C to 40°C (min)	Capacity**	RRP ($)	Cup material***	Lid material***	Dishwasher safe	Replacement parts available
KeepCup Original		8.0	52	78	230mL/8oz, 340mL/12oz, 473mL/16oz	14, 16, 18	Plastic	Plastic	Y	Y
Klean Kanteen Insulated Tumbler		7.2	89	355	230mL/8oz, 473mL/16oz, 591mL/20oz	31.50, 40.50, 49	Stainless steel	Plastic	N	Y
KeepCup Brew		6.4	51	68	230mL/8oz, 340mL/12oz	24, 26	Glass	Plastic	Y	Y
Avanti Go Mug		6.0	54	89	250mL	12.95	Porcelain	Silicone	Y	ns
Cheeki Coffee Mug		5.8	87	337	240mL, 310mL, 350mL	24.95, 26.95, 34.95	Stainless steel	Plastic	Y	Y (lid 350mL only)
Frank Green SmartCup		5.6	54	91	230mL/8oz, 340mL/12oz	32.95, 34.95	Plastic	Plastic	Y	Y
Bodum Travel Mug		5.2	59	131	350mL	25	Plastic	Plastic	Y	ns
Joco Coffee Cup		5.2	52	74	230mL/8oz, 340mL/12oz, 473mL16oz	24.95, 26.95, 28.95	Glass	Plastic	Y	Y
Thermos Thermocafe Travel Mug		2.6	68	194	450mL	17	Stainless steel	Plastic	ns	ns

TABLE NOTES

* See How we test for how we score. 

** Ounces (oz) are displayed where the manufacturer uses ounces on its website. We've included the measurement in mL for easier comparison. 

*** All plastic components are BPA-free. 

ns Not specified. 

Making a difference? 

Is a BYO cup a sustainable step forward? Only if you use it!

According to the KeepCup website, using one of its plastic (LDPe) recyclable KeepCups for a year instead of disposable paper coffee cups will lead to a:

• 36–47% reduction in greenhouse gas emissions
• 64–85% reduction in water use
• 91–92% reduction in landfill. 

A study from the University of Victoria in Canada created a 'break even' matrix for the energy inputs in production of disposable paper cups compared with reusable plastic, glass and ceramic cups.

The table shows how many times you'd have to use your reusable cup for it to become equally energy-efficient to the production of a paper cup.