Most STIs take anywhere from a few days to a few weeks to cause noticeable symptoms, but the timeline varies widely depending on the infection. Some show signs within five days, while others can take months. Perhaps more importantly, many STIs never cause symptoms at all, which means waiting for something to feel wrong is not a reliable way to know if you’re infected.
Chlamydia: 5 to 14 Days
Chlamydia symptoms typically start 5 to 14 days after exposure. You might notice unusual discharge, burning during urination, or pelvic discomfort. But here’s the catch: roughly 77% of all chlamydia infections never produce symptoms. That makes chlamydia one of the most commonly missed STIs, and it’s the primary reason so many cases go untreated. Without testing, most people who have it simply don’t know.
Gonorrhea: 5 to 10 Days
Gonorrhea tends to show up a bit faster in men than in women. Men often develop symptoms within about five days of exposure, usually starting with painful urination and discharge. Women typically see symptoms within 10 days, though the signs can be milder and easier to dismiss as something else, like a urinary tract infection.
About 45% of all gonorrhea cases never become symptomatic. That’s a lower rate of silent infection than chlamydia, but it still means nearly half of people with gonorrhea won’t feel anything unusual. Among untreated cases specifically, 86% were untreated precisely because the person never had symptoms to prompt them to seek care.
Genital Herpes: Around 6 Days
The first herpes outbreak averages about six days after infection. This initial episode is usually the most severe, with painful blisters or sores around the genitals or mouth, sometimes accompanied by flu-like symptoms such as fever and body aches. Later outbreaks, if they happen, tend to be milder and shorter.
Not everyone who contracts herpes gets an obvious first outbreak, though. Some people have such mild symptoms that they mistake them for ingrown hairs or irritation. Others don’t develop a visible outbreak for months or even years after the initial infection, which makes it difficult to pinpoint when they were exposed.
Syphilis: 2 to 3 Weeks
Syphilis follows a staged pattern, and the first sign is a painless sore called a chancre that appears at the site of infection. This typically develops two to three weeks after exposure, though the range can be as short as nine days or as long as 90 days. Because the sore is painless and sometimes hidden (inside the mouth, vagina, or rectum), it’s easy to miss entirely.
If untreated, syphilis progresses through additional stages over months and years, each with different symptoms. The second stage often brings a body rash and flu-like illness weeks to months after the initial sore heals. The infection can then go dormant for years before potentially causing serious damage to the heart, brain, and other organs. Early detection during that first stage makes treatment straightforward.
HIV: 2 to 4 Weeks
Acute HIV infection generally develops within two to four weeks after exposure. During this early stage, some people experience flu-like symptoms: fever, headache, rash, sore throat, and swollen lymph nodes. These symptoms are easy to mistake for a regular illness, and they resolve on their own within a few weeks regardless of whether the virus is treated.
After this acute phase, HIV can remain in the body for years without causing obvious problems. The virus is still active and damaging the immune system during this time, which is why early testing matters far more than symptom monitoring.
Trichomoniasis: 5 to 28 Days
Trichomoniasis, a parasitic infection, has an incubation period of 5 to 28 days. Symptoms often include itching, burning, unusual discharge, or discomfort during urination. Like many STIs, trich frequently goes unnoticed, especially in men, who rarely develop symptoms at all.
Hepatitis B: 2 to 5 Months
Hepatitis B has one of the longest incubation periods of any sexually transmitted infection. Symptoms typically appear about 90 days after exposure, with a range of 60 to 150 days. Early signs include fatigue, nausea, loss of appetite, and jaundice (yellowing of the skin and eyes). Some people clear the virus on their own, while others develop a chronic infection that requires ongoing management.
HPV: Weeks to Months
Human papillomavirus is unpredictable when it comes to timing. If HPV causes genital warts, they can appear anywhere from a few weeks to several months after exposure. Many strains of HPV never cause warts at all. The strains linked to cancer often produce no visible symptoms for years, which is why routine screening (like Pap smears) exists to catch cell changes before they become dangerous.
Why Symptoms Alone Aren’t Enough
The numbers tell a clear story: the majority of chlamydia and a large share of gonorrhea cases produce no symptoms whatsoever. Herpes can hide for months. Syphilis starts with a painless, easily missed sore. HIV mimics the flu. Waiting to “feel something” before getting tested means many infections go undetected long enough to be passed to partners or cause lasting health problems like infertility, chronic pain, or organ damage.
Testing windows matter too. Getting tested too soon after exposure can produce a false negative because the infection hasn’t built up enough to be detected. For most bacterial STIs like chlamydia and gonorrhea, testing is generally reliable about two weeks after exposure. For HIV, most modern tests are accurate within a few weeks, though some antibody-based tests need up to 45 days. Syphilis blood tests typically become reliable within three to six weeks. If you’ve had a specific exposure you’re concerned about, the timing of your test matters as much as getting one at all.