The short answer: the shortest layer of hair should reach the occipital bone. It’s right between where you’re neck and your head connect, and the area just below your ears.

The long answer: Hair extensions can add a lot of length and a lot of volume, but exactly how much is determined by how much natural hair there is. There are also many considerations you must take into account with extremely short hair.

The scalp hair should be thick enough to conceal the extension attachments. Seeing the extension attachment points is not desirable. Short hairstyles such as the pixie cut often don’t have allow enough hair to cover the extensions.

Color differences are more stark with short hair, so be particular about the color.

You’ll probably want to avoid the mullet look. Without proper blending, the gap between the real hair and the extensions will be too drastic. If hair barely reaches the occipital bone, try intermediate length instead of going for an extremely long look. Otherwise, blending can be difficult.

Blending is so important, especially with short hair. Make sure to frame the face and connect the layers, so the extensions are not obvious and look as natural as possible.

Extensions can be installed in very short hair, but blending is crucial. Extensions also shouldn't be installed in thin, short hair.

And remember, your client's hair will still grow while extensions are in!