Quick Tip: What’s the difference between a ballpoint needle and a stretch needle?
Is there even a difference? The answer is yes. I tend to use them interchangeably, but the stretch needles do have some benefits for the extra stretchy fabrics like lycra/spandex.
Both types have a rounded end compared to a universal needle, which prevents snags or runs in the knit fabric. But a stretch needle also allows for a longer thread loop, which is supposed to prevent skipping stitches.
So if you’re using lycra/spandex, I would go with the stretch needle. And when in doubt, take a scrap of the fabric you’ll be using for a project and test out the stitches with various needles to see what gets the best result.