Most sinus infections last 7 to 10 days. The vast majority are caused by viruses and clear up on their own without antibiotics. How long yours sticks around depends on whether it stays viral, turns bacterial, or becomes a longer-lasting chronic problem.
Viral Sinus Infections: 7 to 10 Days
A typical sinus infection starts the same way a cold does, with congestion, facial pressure, and thick nasal discharge. These symptoms usually peak around days 3 to 5 and then gradually improve. By day 7 to 10, most people feel noticeably better or are fully recovered. Because viruses cause the overwhelming majority of sinus infections, this is the timeline most people will experience.
Children follow roughly the same pattern. Runny nose, congestion, and mild cough lasting beyond 7 to 10 days are the main signs that a child’s illness has moved beyond a simple cold into sinus infection territory.
When a Bacterial Infection Takes Over
About 2% of viral sinus infections develop a bacterial component. The clearest sign is symptoms that persist beyond 10 days without any improvement. But there’s another telling pattern worth knowing: “double sickening.” This is when you start to feel better after the first few days, then around day 5 or 6, your symptoms suddenly get worse again. New facial pain, a fresh wave of thick discolored discharge, or a returning fever after things seemed to be improving all point toward a bacterial infection settling in.
A third scenario involves severe symptoms from the start. If you develop a fever of 102°F or higher along with significant facial pain and thick, discolored nasal discharge lasting at least 3 to 4 days, that also suggests bacteria rather than a virus.
Bacterial sinus infections typically last longer than viral ones and are the main reason doctors sometimes prescribe antibiotics. Even with antibiotics, though, the benefit is modest. In clinical trials, people taking antibiotics for bacterial sinusitis recovered in an average of about 8 days, compared to roughly 11 days for those on placebo. That’s only a 2 to 3 day difference, which is why many doctors recommend waiting and managing symptoms before reaching for a prescription.
Subacute and Chronic Sinusitis
If your symptoms drag on past the typical 10-day window but eventually resolve within about 4 weeks, that still falls under acute sinusitis. Symptoms lasting between 4 and 12 weeks are sometimes called subacute sinusitis, a middle ground between a short-lived infection and a truly chronic one.
Chronic sinusitis is defined as sinus inflammation lasting at least 12 weeks. At that point, the problem is less about a single infection and more about ongoing inflammation in the sinuses that doesn’t resolve. People with chronic sinusitis typically deal with persistent congestion, reduced sense of smell, facial pressure, and thick drainage that just won’t quit. The causes are more complex, often involving nasal polyps, structural issues, allergies, or immune system factors rather than a straightforward infection.
There’s also a pattern called recurrent acute sinusitis, where someone gets four or more separate sinus infections in a single year, with full recovery between each episode. The individual infections follow the normal 7 to 10 day course, but they keep coming back.
What Affects How Long Yours Lasts
Several factors influence your personal timeline. Allergies can keep your sinuses inflamed and slow drainage, giving infections more time to linger. Smoking or regular exposure to secondhand smoke irritates the sinus lining and interferes with the tiny hair-like structures that sweep mucus out. Structural issues like a deviated septum or nasal polyps can physically block drainage pathways, creating an environment where infections take longer to clear.
Your immune system matters too. People who are immunocompromised or dealing with conditions like cystic fibrosis tend to have longer, more complicated sinus infections. Even something as simple as dry indoor air during winter can thicken your mucus and slow recovery.
Signs Your Infection Needs Attention
Most sinus infections resolve without medical treatment. But certain symptoms signal that the infection may be spreading beyond your sinuses into nearby structures like the eye socket or the lining of the brain. Swelling or redness around the eyes, a severe headache that doesn’t respond to typical pain relievers, swelling of the forehead, double vision, confusion, or a stiff neck all warrant immediate medical evaluation. A high fever (102°F or above) that persists for several days alongside worsening sinus symptoms is another red flag.
For more routine cases, the 10-day rule is a useful guide. If your symptoms haven’t improved at all after 10 days, or if they improve and then worsen again around day 5 or 6, a doctor can evaluate whether antibiotics would help. Otherwise, saline rinses, staying hydrated, using a humidifier, and over-the-counter decongestants or pain relievers are typically enough to get you through the week or so it takes for a viral sinus infection to run its course.