Depending on the type of finch, they can be kept in a variety of cages or aviaries, big or small. For pet store finches, a 24-inch cage is large enough for two small birds. They will breed in this size pen but as the number of finch's increase, the size of the cage must also increase. Also, if there are praying animals present, such as cats, it would be prudent to hang the cage from the ceiling to reduce stress to the birds. All birds that are kept in a cage tend to spit the husks of their seed, causing spillage on whatever is below the cage. Since the birds are flying animals, they should have some flying time, perhaps in and enclosed room at least some of the time.
As variety of seeds are the mainstays of a finch's diet, they do occasionally love treats. Fruits and vegetables are sometimes appreciated as well as honey or fruit sticks. Millet, dandelion leaves, an aloe vera plant or certain grasses can be grown especially for the birds. Fresh water each day is a basic necessity for the birds and can be served in a variety of acceptable dishes. Gravel bought at the pet store is also required for the birds because they need this for digesting their foods. As with all birds, finch should have access to some form of calcium such as a cuttlebone from the pet shop or shell of some sort. Hens egg shells are fine but should be heated to kill possible bacteria on them.
A finch likes to bathe, so keeping a bird bath available for them is, if not necessary, a well-appreciated accessory. It is however, necessary to keep the water fresh and clean because they will relieve themselves in it, thus contaminating the water.