I get asked this question often, and the answer is no. there is no such breed as a Teacup Yorkshire Terrier. According to the breed standard a Yorkshire Terrier weighs 7 pounds and less and there is no distinction for dogs of a smaller size. No matter how small a Yorkie is, it is still just a Yorkshire Terrier. You will never see the breed listed as “Teacup Yorkshire Terrier“ on a dog’s registration papers.
Simply put, teacup is an adjective. It is no different than the word pretty, cute, small, baby doll, tiny, mini, etc. that has been placed in front of Yorkshire Terrier as a descriptive measure. A great deal of breeders and buyers get caught up in the controversy of advertising, and the use of words like teacup, toy, mini, micro are simply a means of describing size. Teacup or Toy Yorkshire Terriers simply do not exist, though the size difference of Yorkies can vary to a degree. There is only one Yorkshire Terrier classification, the Yorkshire Terrier is a toy breed, and there is no such breed as Teacup, T-cup, Toy or Miniature Yorkshire Terrier.
With that being said, I do realize that a great number of individuals do have a preference for a Yorkie of a particular size. For that reason I do post estimated adult weight along with the pictures of my puppies. I do this instead of labeling my puppies as toy, teacup, micro, mini or pocket because I have found that these terms mean different things to different people. I prefer to avoid the confusion these labels can cause.
Let good common sense be the judge rather than allowing adverting techniques to determine the type of Yorkie you would like. A Yorkie that looks fragile and sickly probably is. Good quality breeders produce well adjusted, healthy puppies regardless of size. Remember, size can NEVER be guaranteed. You may end up with a 6 lb "teacup" if you aren't careful. Also, breeder records are invaluable as to what size dogs any Dam / Sire combination may produce. If size is a determining factor, a good quality breeder will have a fairly good idea of approximate adult weight.
I use a growth chart on which I track weight from birth, yet no one can do any better than an educated guess as to the size of a mature Yorkie. It is simply not a realistic expectation. However, many breeders can give an average or approximate weight, but size can never be guaranteed.
Some breeders, as well as myself occasionally have puppies that may weigh less than 4 lbs at maturity. (The word "teacup" is sometimes used to describe a Yorkie that will be less than 4 lbs.) If a small Yorkie is healthy and well adjusted, adoption shouldn’t be a problem. These tiny puppies do require more time and occasionally more frequent vet checks. Reputable breeders do not intentionally gear their program around producing puppies that are less than 4 lbs. The key is finding a reputable breeder that gears their breeding program around producing healthy quality Yorkshire Terriers, regardless of size. Puppies on the small side from really good kennels tend to fair much better than those from kennels that focus their breeding program around producing the fragile “teacups.” The best reference guide is a veterinarian specializing in small breed animals. They can give you the information you need to decide if a very small Yorkie is for you.
If small children are in the house, a very small Yorkie is not for you! If the Yorkie is purchased as a companion for a single person or couple, then considering a smaller dog is not a bad idea.
So, Yes I do sometimes have smaller size puppies available, but availability varies from litter to litter. Remember, there is no way to guarantee the exact adult weight of a puppy, I can only estimate based on experience, past litters, size of the parents and puppies current size and/or weight. My Yorkshire Terrier puppies do conform to the AKC breed standard of no more than 7 lbs.