How Long a Cold Lasts in Babies
Medically reviewed by Dr. Michael Okonkwo, MD, FAAP · Board-Certified Neonatologist
Content reviewed against published AAP, NIH, AAP guidelines
Last reviewed:
If your baby has been diagnosed with or you suspect how long a cold lasts in babies, here is what the evidence says.
The short answer
The common cold in babies typically lasts 7 to 10 days, though some symptoms like a residual cough or runny nose can linger for up to two weeks. Symptoms usually peak around days 2 to 3 and then gradually improve. Babies may catch 8 to 10 colds per year in their first two years, which is completely normal and helps build their immune system.
Key takeaways
- The common cold in babies typically lasts 7 to 10 days, though some symptoms like a residual cough or runny nose can linger for up to two weeks. Symptoms usually peak around days 2 to 3 and then gradually improve. Babies may catch 8 to 10 colds per year in their first two years, which is completely normal and helps build their immune system.
- Usually normal when: The cold follows the expected timeline: worsening for 2-3 days, then gradually improving over the next 5-7 days
- Call your doctor if: Your baby has difficulty breathing - fast breathing, flared nostrils, rib retractions, or wheezing - or refuses to drink fluids
- Varies by age — see the age-by-age breakdown below
“Fever itself is not an illness — rather, it is a sign or symptom that the body is fighting an infection. Fever stimulates certain defenses, such as the white blood cells, which attack and destroy invading bacteria.”
Parents everywhere have the same worry. You are doing the right thing by looking into it.
What Parents Should Know
According to AAP, NIH guidelines, the common cold in babies typically lasts 7 to 10 days, though some symptoms like a residual cough or runny nose can linger for up to two weeks. Symptoms usually peak around days 2 to 3 and then gradually improve. Babies may catch 8 to 10 colds per year in their first two years, which is completely normal and helps build their immune system. At 0-3 months, newborns are obligate nose breathers, so even a mild cold can cause significant feeding and sleeping difficulties. Nasal congestion at this age should be managed with saline drops and gentle suction. Any fever (100.4°F / 38°C or higher) during a cold in a baby under 3 months requires immediate medical evaluation, as it could indicate a more serious infection. It is generally considered normal when the cold follows the expected timeline: worsening for 2-3 days, then gradually improving over the next 5-7 days. However, you should contact your pediatrician promptly if your baby has difficulty breathing - fast breathing, flared nostrils, rib retractions, or wheezing - or refuses to drink fluids.
Normal vs. Concerning
By Age
What to expect by age
0-3 months
Newborns are obligate nose breathers, so even a mild cold can cause significant feeding and sleeping difficulties. Nasal congestion at this age should be managed with saline drops and gentle suction. Any fever (100.4°F / 38°C or higher) during a cold in a baby under 3 months requires immediate medical evaluation, as it could indicate a more serious infection.
3-6 months
Colds at this age follow a typical pattern: runny nose and mild fussiness for the first 2-3 days, peak congestion around days 3-4, then gradual improvement. The nasal discharge often starts clear, turns thick and yellow or green (which is a normal part of the immune response, not necessarily a sign of bacterial infection), and then clears. Using a cool-mist humidifier and keeping baby upright during feedings can help.
6-12 months
As maternal antibodies wane and babies put everything in their mouths, cold frequency increases. A cold lasting 7-10 days is normal; however, if symptoms worsen after day 5 or a new fever develops after initial improvement, this may indicate a secondary infection like an ear infection. Babies this age may also refuse solids during a cold but should still be taking breast milk or formula.
12-36 months
Toddlers in group care settings may seem to have a nearly constant runny nose through fall and winter. Each individual cold should still follow the 7-10 day timeline. A cough from postnasal drip can persist for 2-3 weeks after other symptoms resolve. Honey (for children over 12 months) can soothe a cough, but over-the-counter cold medicines are not recommended for children under 4 years.
What to Tell Your Pediatrician
- Describe when you first noticed how long a cold lasts in babies and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if the cold is not improving at all after 10 days, or symptoms worsen after initial improvement.
- Mention if your baby develops a new fever on day 5 or later of the cold, which may suggest a secondary infection.
- Bring a list of any questions or observations you want to discuss at the appointment.
What Should You Do?
When to take action
- The cold follows the expected timeline: worsening for 2-3 days, then gradually improving over the next 5-7 days
- Nasal discharge changes from clear to yellow or green and back to clear - this color change is a normal part of the immune response
- Your baby has mild fussiness but is still feeding reasonably well and producing wet diapers
- A mild cough lingers for up to 2 weeks after the worst of the cold has passed
- The cold is not improving at all after 10 days, or symptoms worsen after initial improvement
- Your baby develops a new fever on day 5 or later of the cold, which may suggest a secondary infection
- Your baby is coughing enough to cause vomiting or is having difficulty sleeping despite home remedies
- You notice thick, persistent green nasal discharge for more than 10-14 days
- Your baby has difficulty breathing - fast breathing, flared nostrils, rib retractions, or wheezing - or refuses to drink fluids
- Any fever in a baby under 3 months, or a fever above 104°F (40°C) in older babies that does not respond to medication
What You Can Do at Home
- Keep track of when you notice how long a cold lasts in babies — noting the time of day, duration, and any triggers can help your pediatrician.
- Remember that the cold follows the expected timeline: worsening for 2-3 days, then gradually improving over the next 5-7 days — this is generally within the range of normal.
- At 0-3 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
- Follow any care instructions from your pediatrician. Keep a written log of symptoms to bring to appointments.
- While monitoring at home, seek immediate care if your baby has difficulty breathing - fast breathing, flared nostrils, rib retractions, or wheezing - or refuses to drink fluids.
Related Resources
Frequently asked questions
Is how long a cold lasts in babies normal?
When should I call the doctor about how long a cold lasts in babies?
When is how long a cold lasts in babies normal?
What causes how long a cold lasts in babies?
What should I mention to my pediatrician about how long a cold lasts in babies?
Is how long a cold lasts in babies normal at 0-3 months?
Is how long a cold lasts in babies normal at 3-6 months?
Should I go to the ER for how long a cold lasts in babies?
Does how long a cold lasts in babies go away on its own?
References
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss How Long a Cold Lasts in Babies.
Things to mention
- Describe when you first noticed how long a cold lasts in babies and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if the cold is not improving at all after 10 days, or symptoms worsen after initial improvement.
- Mention if your baby develops a new fever on day 5 or later of the cold, which may suggest a secondary infection.
- Bring a list of any questions or observations you want to discuss at the appointment.
Observations to share
- The cold is not improving at all after 10 days, or symptoms worsen after initial improvement
- Your baby develops a new fever on day 5 or later of the cold, which may suggest a secondary infection
- Your baby is coughing enough to cause vomiting or is having difficulty sleeping despite home remedies
Urgent signs to report immediately
- Your baby has difficulty breathing - fast breathing, flared nostrils, rib retractions, or wheezing - or refuses to drink fluids
- Any fever in a baby under 3 months, or a fever above 104°F (40°C) in older babies that does not respond to medication
My notes
From ismybabyalright.com — free, evidence-based baby health guides
All content follows our editorial policy and is reviewed against published clinical guidelines.
2,705 evidence-based guides6 authoritative medical sources5 medical advisory board members
Related Resources
Bottom line
Most cases of how long a cold lasts in babies are normal. Talk to your pediatrician if your baby has difficulty breathing - fast breathing, flared nostrils, rib retractions, or wheezing - or refuses to drink fluids.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.
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