What Are Irish Curls? Understanding Your Hair Type

Irish curls describe hair with two textures at once — straighter waves on top and tighter curls underneath.

You brush out your hair, and the crown falls flat within an hour while the hair at your nape coils into tight spirals you never asked for. That mismatch has a name: Irish curls. The term covers hair with mixed texture, usually smoother through the top layers and wavier or curlier below, and it is increasingly the phrase people use to describe the pattern they have been fighting with a flat iron for years. What follows explains where the pattern comes from, how to tell it apart from heat or bleach damage, and how to cut and style it so both textures stop competing.

What Are Irish Curls, Exactly?

Irish curls are a descriptive term for uneven or double-textured hair, not an official curl category. The standard curl-typing system runs from Type 1 (straight) through Type 4 (coily), and it assumes one pattern across the head. Irish curls break that assumption, describing where texture varies rather than a single strand shape.

Most accounts put the top layers somewhere between straight and loose waves, with the lower layers landing in wave-to-curl territory. One stylist breakdown gives a rough range of 1B–2B on top and 2B–3B underneath, though that span is a description, not a rule.

Worth knowing: “Irish curls,” “Irish waves,” and “Irish hair” get used interchangeably in most coverage. None of them are standardized technical terms, which is why you will not find them in a curl-typing chart.

The name reflects an association with Irish and Celtic heritage, not a restriction. Anyone can carry this pattern — the genes responsible do not check ancestry.

Where The Texture Difference Comes From

Genetics explain most cases. Hair shape is set by the follicle, and different follicles across the scalp can produce different shapes. Areas that grow flatter strands sit next to areas that grow curved ones, and you get a head with two patterns living on it.

The split usually shows up most clearly from the occipital bone down — the bump at the back of your skull. Hair above that line tends to be smoother; hair below it, especially at the nape, tends to be tighter.

There is a second possibility worth ruling out. Bleach, heat styling, and general damage can create or exaggerate a mixed look, because damaged sections lose their bend while healthier sections keep theirs. If your texture changed after a color service or a few months of daily flat-ironing, damage may be doing more of the work than genetics.

One quick check: look at your hair while it is soaking wet and unstyled. Natural Irish curls show both patterns even when wet. Damage-driven variation often shows curls underneath and a limp, stretched top that will not hold a wave no matter what you do.

How To Cut And Style Irish Curls

Cut and style for the hidden pattern, not the visible one. Stylists who work with this texture consistently say the same thing: if you treat the straighter top layer as your whole head, the underneath texture gets weighed down, and you end up with a flat crown over frizz.

• Ask for layers. A layered cut removes weight so the lower curls can spring up without pulling the top flat.
• Style in two passes. Apply a curl cream or gel to the wavy and curly sections, then use a lighter product with soft hold on the canopy.
• Dry upside down or with a diffuser. Encouraging the underneath texture while it dries keeps the two zones from separating visually.
• Resist the flat iron on the crown. Smoothing the top makes the contrast sharper, not softer.

If you are rebuilding a routine from scratch, this roundup of tested products for Irish curls covers the creams, gels, and diffusers that work on mixed texture without flattening either layer.

Product choice matters more here than for single-texture hair, because one formula rarely serves both zones. The most common mistake is buying for the curl type you wish you had, then wondering why the crown falls flat by lunch. The full explanation of why this pattern behaves the way it does is documented in InStyle’s guide to Irish curls and hair cuts, which covers the cut-and-style approach in detail.

Common Mistakes Worth Avoiding

Most frustration with this hair type traces back to three assumptions. Drop them and the routine gets simpler.

• Assuming the straight top means straight hair. The top layer masks texture below. Styling for only what you see leaves the rest of your head unmanaged.
• Treating it as a fixed curl type. Irish curls are a mixed-texture description, so there is no number to match. Formulas built for one curl type will underperform on half your head.
• Blaming everything on genetics. Bleach and heat damage mimic and amplify uneven texture. Ruling that out first tells you whether you need a repair plan or a styling plan.

One useful reframe: the uneven pattern is not a defect to correct. It is the shape your hair grows in, and a cut designed around it tends to look intentional rather than accidental.