When Do Babies Start Smiling and Laughing? | First Smiles

You watch your newborn’s face during sleep, and a tiny smile flickers across their lips. It’s easy to think they’re having a happy dream. But those early grins are usually reflexes, not emotional responses. The real milestone — the one that makes your heart skip — is the social smile, which happens intentionally in reaction to you.

The social smile typically arrives by the end of the second month, around 8 weeks. Laughter, which requires more brain development, emerges between 4 and 6 months. This article walks through the difference between reflex and social smiles, what to expect week by week, and when a delay might warrant a call to your pediatrician.

The Difference Between Reflexive and Social Smiles

Reflexive smiles are involuntary and brief. They happen during sleep or when your baby passes gas. These random grins are triggered internally — not in response to you.

A social smile is different. It’s a deliberate reaction to your face or voice. Your baby’s eyes light up, and the grin lasts long enough to feel meaningful. This milestone signals that your baby is beginning to engage socially.

Understanding the difference helps you know when your baby is truly connecting. It also guides pediatricians in tracking development. The American Academy of Pediatrics notes that the social smile sets the foundation for later social and emotional skills.

Why Parents Watch for That First Real Grin

That first intentional smile feels like a big moment — and it is. It marks the start of your baby’s social communication. But the timing can vary, and many parents wonder if their baby is on track or if a late smile signals a problem.

• Individual variation: Every baby develops at their own pace. Some smile at 6 weeks, others closer to 10 weeks. Premature babies may need extra time to reach this milestone based on adjusted age.
• Reflexive smiles cause confusion: Newborns make lots of reflex smiles, so caregivers may mistake a gas grimace for a real social response. This can make it hard to tell when the true milestone arrives.
• Laughter comes later: While social smiling is a 2-month milestone, laughter typically doesn’t appear until 4 to 6 months. Parents sometimes worry if giggles are delayed even though smiles are on track.
• Temperament plays a role: Some babies are more serious and smile less frequently. A lower frequency of smiling does not necessarily indicate a problem, as long as the baby does smile in response to interaction.
• Cultural influences: Parenting styles and cultural norms can affect how often babies see smiling faces. However, the underlying ability to smile socially emerges around the same time across cultures.

Most babies will hit the social smile milestone by 2 to 3 months. If your baby isn’t smiling by 2 months, it’s a good idea to mention it to your pediatrician. But don’t overcompare with other babies — development is rarely a straight line.

The Timeline for Smiling and Laughing

The first social smile tends to appear around 8 weeks, though some babies flash it as early as 6 weeks or as late as 10 weeks. Cleveland Clinic defines the social smile as an intentional, responsive expression. Before this, smiles are mostly reflexive.

Around 2 to 3 months, babies start engaging in “smile conversations” — they smile back when you smile at them. This back-and-forth is a key social-emotional milestone that shows your baby is connecting with you.

Laughter typically begins between 4 and 6 months. It often starts with a chuckle or a giggle in response to playful interactions like peek-a-boo. By 6 months, many babies laugh frequently during social play.

These are average ranges. Your baby may reach smiling or laughing a bit earlier or later without concern. Premature babies often hit social milestones on their adjusted age rather than birth age.

Encouraging Your Baby’s Smile

You can’t force a social smile, but you can create an environment that invites it. Babies smile in response to warm, engaging interactions. Try these simple ways to encourage that first grin.

1. Make eye contact and smile first: Babies mimic expressions. When you smile at them, they are more likely to try to smile back. Hold your face close to theirs — newborns focus best at about 8 to 12 inches.
2. Use a high-pitched, animated voice: Infant-directed speech captures your baby’s attention. Pair it with an exaggerated smile to increase the chance of a response.
3. Play gentle games: Peek-a-boo, gentle pat-a-cake, or making funny sounds can trigger a smile or laugh. These games simulate social interaction and encourage your baby to engage.
4. Respond to their coos and smiles: When your baby makes a sound or smiles, respond immediately with a smile or a word. This teaches them that their social signals have an effect.
5. Give it time and don’t overdo it: Babies get overstimulated easily. If your baby looks away or becomes fussy, take a break. Short, frequent interactions work better than long attempts.

Remember, the social smile is a developmental milestone that emerges naturally. Your loving attention simply invites it. If your baby isn’t smiling by 2 months, don’t blame yourself — some babies just need a little more time or a check-in with the pediatrician.

When to Talk to Your Pediatrician

If your baby hasn’t shown a social smile by 2 months, mention it during your 2-month well-child visit. The American Academy of Pediatrics lists lack of social smiling by 2 months as a reason to talk with your provider. An NIH study supports using smiling as a developmental red flag.

By 6 to 8 months, a failure to smile is considered a developmental red flag that warrants a formal assessment. The NHS red flags guide includes lack of smiling at this age as a prompt for referral.

If you notice delays in more than one area — such as smiling and motor skills — a referral is recommended. Early intervention can be helpful, and most delays are minor or temporary.

These guidelines are here to help, not to worry you. Most babies who smile late catch up. But if your intuition says something is off, trust it and ask.

The Bottom Line

Babies typically start social smiling by about 2 months and begin laughing around 4 to 6 months. Reflexive smiles are not social smiles. If your baby isn’t smiling by 2 months, mention it to your pediatrician. Many babies develop at their own pace, but early intervention can help if needed.

If your baby was born prematurely, your pediatrician will adjust milestone expectations based on adjusted age — that conversation is part of routine care.