I think it will be too big. The neck is 4 1/2" across. The arm holes are 4" across. It is 10 1/2" from top to bottom. It is 11 1/2" across the bottom ruffle. It was snug on my 15 lb dachshund.
well. i wouldnt consider my chihuahua small. she is pretty big for a chihuahua. so i'm bidding!lol if i win and it is too big...back to listia it will go. : P