As life decisions go, gaiwan versus teapot might not be keeping you up at night, but it's consequential in the world of tea.
white2tea is here to save you from unnecessary teaware tuition - purchasing equipment that you quickly outgrow in your tea journey.
As a general beginner's recommendation for your very first vessel, most people won't go wrong with a 100 ml (3.5 oz) gaiwan or teapot. Either will do the job. Gaiwans are pretty much guaranteed to work for every tea. Teapots have their advantages but can be hit-or-miss.
Ease of pouring technique
Gaiwans have a small learning curve to master and a slightly higher risk of burning your fingers with hot tea as you build the skill.
Teapots are easier to use than gaiwans. The technique is intuitive and teapots can be more forgiving for hands that shake or have arthritis. People who struggle with fine motor skills because of disabilities or any other reason may prefer teapots.
Filters, pour times, and clogging
Some teapots have a built-in filter that helps prevent leaf bits from ending up in your cup. The large opening of a gaiwan is likelier to let a few leaves out, especially with fine teas like bud-heavy jinjunmei black tea.
Teapots usually have pour times of 7-10 seconds and a teapot filter or spout hole can clog if you pour too aggressively (adding frustration and making pour time even longer).
Rinsing your teas and the initial gongfu style infusions may call for "flash steeps" of a few seconds or less. Gaiwans can pour instantly and can't be clogged, so it's easier to avoid oversteeping your tea.
Because gaiwans pour faster with more control over steep time, they can be more useful for evaluating teas. This is true for beginners as well as experienced tea drinkers trying new teas.
Heat retention
Some teas love heat. Some teas require long, hot steeps to extract all the goodness. Those teas can work better in teapots than in gaiwans.
The physics of teapots usually retain heat better than gaiwans - shape, lid size, surfaces, wall thickness. You can also shower a teapot exterior with boiling water to maintain a higher infusion temperature inside. (Don't @ white2tea and naysay. We've proven this with a thermometer.)
If you've got your hands on an aged puerh tea or aged white tea - or any high endurance tea that benefits from longer gongfu steeps (60+ seconds) - a teapot may be the superior choice.
Ease of clean-up
Gaiwans are much easier to empty and clean after your session. Just dump the leaves out. Teapots need more attention to detail and extra rinsing.
Portability
Gaiwans are more compact and less fragile than teapots because they lack handles and spouts. Either vessel type can be part of a tea travel set but a kit with a teapot ends up bulkier.
Value and quality
Gaiwans are a safe bet. A cheap gaiwan might be gaudy or slightly awkward, but it'll get the job done. They just work. Maximum value for functionality.
We love teapots, but cheap teapots that work well are less common. There's more to get wrong in the design. Even pricier teapots sometimes leak, spill, or pour very slowly.
Water capacity and sharing with others
For gongfu style tea sessions, 100 ml (3.5 oz) is a middle ground for both gaiwan size and teapot size. Not overwhelming for solo sessions but enough volume to share with two or three other people.
With a teapot, you can pour each infusion directly into multiple small cups Chaozhou style to share without using a cha hai (literally "sea of tea") or gong dao bei (sharing pitcher).
Using a gaiwan, you'll either pour directly into one larger cup (for solo drinking) or else you'll need to pour into a sharing pitcher from the gaiwan, then distribute tea to several smaller cups using the pitcher.
Very large vessels of 250-300+ ml (8.5-10+ oz) are less practical for small-group gongfu tea sessions. However, this is an excellent teapot size if you prefer brewing tea western-style with milder leaf ratios and longer steeps.
If you don't have a group, large gaiwans can be handy for solo sipping grandpa style with a few grams of leaves brewing directly in the vessel. Use the lid to keep the leaves in the bowl as you sip.