What is pilonidal sinus?
A pilonidal sinus is a small hole or tunnel in the skin at the top of the cleft between the buttocks, thought to develop when loose hairs pierce and burrow under the skin. It may cause no trouble for long periods, then flare into a painful abscess or discharge fluid persistently. Recurrent infection is common once a sinus has formed.
The condition most often affects younger adults, particularly men between their late teens and thirties, and is more common in people with coarse body hair, those who sit for long periods, and where there is a family tendency. Diagnosis is made by simple examination of the area; scans are rarely needed. Treatment ranges from managing acute abscesses to planned surgery to remove or clean out the sinus tracks.
Common symptoms
- A small pit or opening in the skin at the top of the buttock crease
- Recurring pain and swelling in the area
- Discharge of fluid or pus, sometimes blood-stained
- An unpleasant smell from the discharge
- A tender, hot lump when an abscess forms
- Difficulty sitting comfortably during flare-ups
How long will you wait?
Routine NHS waits for planned pilonidal surgery commonly run to four to nine months at many trusts, although abscesses are drained urgently as emergencies when they occur.
Privately, you can typically see a consultant within 3–7 days, with planned surgery usually scheduled within 2–4 weeks.
NHS England median referral-to-treatment wait: 12.4 weeks, with 2.5 million people waiting over 18 weeks (May 2026). Individual waits vary by trust and urgency.
Treatment options
- Incision and drainage. An infected abscess is drained under anaesthetic, relieving pain quickly, though the underlying sinus often persists.
- Minimally invasive techniques. Options such as pit-picking or endoscopic (EPSiT) treatment clean out the tracks with tiny incisions and faster healing.
- Excision surgery. The sinus and its tracks are removed; the wound is either stitched closed, sometimes with an off-midline flap, or left open to heal gradually.
- Laser hair removal. Removing hair from the area reduces the chance of the sinus recurring after treatment.
What does private treatment cost?
As a guide, private pilonidal sinus surgery typically costs around £2,500–£4,000 in the UK in 2026, depending on the technique and the extent of the disease.
Does health insurance cover pilonidal sinus?
Private medical insurance usually covers drainage of an acute pilonidal abscess and definitive surgery for a sinus that first appears after your policy begins, as this is an acute surgical condition. If you had flare-ups or a known sinus before taking out cover, expect it to be excluded as pre-existing initially. Because recurrence is relatively common, check whether further operations for the same sinus would be covered under your policy's terms.
Frequently asked questions
Will a pilonidal sinus go away on its own?
Occasionally a sinus stays quiet for years and causes no trouble, and a symptom-free sinus found incidentally does not need surgery. However, once a sinus has become infected or discharges regularly, it rarely resolves permanently by itself, and each abscess tends to be followed by others. Planned surgery is usually recommended after recurrent infections to remove or clean out the tracks properly.
How long does the wound take to heal after surgery?
It varies with technique. Minimally invasive procedures and wounds closed with stitches often heal within two to four weeks. Where the wound is left open to heal from the base, which reduces recurrence in some cases, healing takes six to twelve weeks with regular dressing changes. Your surgeon will explain the trade-offs; sitting and driving are uncomfortable for the first couple of weeks either way.
How can I stop the sinus coming back?
Recurrence affects a meaningful minority of patients whatever operation is used, so prevention matters. Keeping the area clean and dry, and crucially keeping it free of hair, by shaving, depilatory cream or laser hair removal, substantially reduces recurrence. Avoiding very prolonged sitting where practical also helps. Many specialists now recommend a course of laser hair removal after the wound has healed.