Thread Veins vs Varicose Veins: How to Tell the Difference

The key difference is this: thread veins are small surface vessels (often cosmetic), while varicose veinsare larger veins caused by valve failure (venous reflux) and are more likely to cause symptoms and long-term skin changes.

Quick comparison

What do thread veins look like?

Thread veins (also called spider veins or telangiectasia) are small, visible veins close to the skin surface. They often look like fine red, purple or blue lines, sometimes in a spider-web pattern.

They’re very common and are often treated for cosmetic reasons. However, in some people they occur alongside underlying venous reflux.

What do varicose veins look like?

Varicose veins are larger, bulging veins that develop when the valves inside a vein stop working properly. Blood flows the wrong way (reflux), pressure builds up, and the vein stretches.

They may be obvious on the surface, or they can be “hidden” deeper under the skin — still causing symptoms.

Symptoms: what should you pay attention to?

If you have visible veins plus any of the symptoms below, it’s worth getting assessed:

• Aching or heaviness in the legs (often worse later in the day)
• Swelling around the ankles
• Itching, burning or tenderness over veins
• Night cramps or restless legs
• Skin changes (eczema-like rash, brown staining, thickening)
• Bleeding from a vein or a hard, tender lump (phlebitis)

Do you need an ultrasound scan?

A duplex ultrasound is the gold-standard test for venous reflux. You don’t always need a scan for purely cosmetic thread veins, but it’s often recommended if you have symptoms, visible varicose veins, or signs of venous disease.

Treating visible thread veins without addressing underlying reflux can lead to disappointing or short-lived results.

Treatment options (in plain English)

Thread veins

• Microsclerotherapy: tiny injections to close thread veins so they fade over time.
• Laser: sometimes used for very fine veins or facial thread veins.

Varicose veins

• Radiofrequency ablation (RFA): seals the main faulty vein using controlled heat.
• Foam sclerotherapy: injection treatment to close selected veins.
• Avulsions (phlebectomy): removes bulging surface veins through tiny incisions.

Helpful next steps

If you’re not sure what type of veins you have, start with a specialist assessment. It’s the quickest way to get clarity and avoid unnecessary treatment.