18-month sleep regression

At 18 months old, most toddlers are sleeping through the night. So if your toddler starts waking often or resisting falling asleep, it can be confusing and frustrating. Known as a sleep regression, this temporary sleep setback can be triggered by developmental milestones, changes in your toddler's routine, illness, or teething. A consistent routine and lots of patience can get you through this difficult phase.

A toddler laying down with their feet sticking out of a crib
Photo credit: © Courtney Rust / Stocksy United

Most parents expect their toddlers to sleep better than newborns, but a sleep regression can turn those expectations on their heads. If your little one once slept well but is now struggling to fall asleep or wakes frequently throughout the night, you might be dealing with sleep regression.

This phase of your child's life is temporary, but it can be challenging when you fail to get enough sleep night after night. There are various reasons why an 18-month-old might experience a sleep regression, including developmental milestones, illness, and changes in routine.

Advertisement | page continues below

Getting through this challenging time in your toddler's life takes a lot of patience. Here's how you can encourage your toddler to start sleeping well again.

(And for more in-depth information about sleep regressions, as well as how to combat them, check out Baby Sleep 101Opens a new window from BabyCenter Courses.)

What causes the 18-month sleep regression

At 18 months old, your child is experiencing many changes, both in themselves and the world around them! Toddlers need a lot of sleep to keep up their high-energy lifestyle filled with learning and fun, so any setback in their sleep schedule can turn them into cranky kids.

Here are some reasons a toddler who typically sleeps soundly might experience an 18-month sleep regression.

  • Milestones. You've been cheering your toddler on while they learn new skills, like walking and talking, but these developmental milestones may also disrupt their sleep. The excitement of practicing these skills can keep your little one up at night, and you might notice your child moving around more in bed or chattering on when they should be sound asleep.
  • Separation anxiety. It's normal for children to experience separation anxiety – and while it often starts as early as 8 or 9 months, it peaks between 12 and 24 months. Your little one might get stressed or anxious when you leave after putting them down for a nap or bedtime, keeping them from getting the rest they need.
  • Changes in routine. If your family traveled recently, missed a few naps, or went to bed late, these changes in routine could be the culprit behind their sleep regression. Babies and toddlers thrive on routine, and changing things could disrupt their sleep patterns.
  • Nap changes. At 18 months old, your toddler is likely transitioning from two naps per day to just one, which could cause a temporary disruption in their sleep routine.
  • Illness or discomfort. At 18 months old, your toddler might be teething. The discomfort caused by the eruption of canines and molars could wake them or make it hard to settle into sleep. If they've been sick, this can cause sleep problems, too.
  • Nighttime fears. Your toddler's developing imagination might inspire some new worries, like the dark and monsters.

18-month sleep regression signs

How do you know if your 18-month-old is experiencing a sleep regression? In general, anytime a child's sleep habits change for the worse for more than a day or two at a time, it's probably a sleep regression.

At 18 months old, your little one needs 13 to 14 hours of sleep daily. If your toddler was a healthy sleeper but suddenly doesn't sleep as well, here are some signs it's a sleep regression:

Advertisement | page continues below
  • They wake multiple times a night for more than a few days.
  • They fuss and seem wide awake when it's bedtime or naptime.
  • They sleep more during the day and are fussier than usual, since they aren't getting enough sleep at night.

How long does the 18-month sleep regression last?

There isn't a typical time frame for how long a sleep regression lasts. Each child is different, and the road back to sleeping soundly varies.

Some sleep regressions last only a few days, while others may go on for a few weeks depending on the cause, your child's development, and any other underlying issues. How you respond to disruptions in your child's sleep could help speed things up and get you back to sleeping through the night. But sometimes, it's just a matter of waiting things out with a lot of patience.

If you've done everything you can to help your child get back on a regular sleep schedule and they still aren't sleeping well after four weeks, bring it up with their doctor. You may also need to see them sooner if you're worried about any underlying medical problems.  Their doctor will be able to help identify and treat other issues contributing to their sleep regression.

Sleep regressions can happen any time, but especially at 4 months, 6 months, 8 months, and 12 months.

Advertisement | page continues below

How to cope with the 18-month sleep regression

If sleepless nights and skipped naps have you pulling your hair out, here are a few ideas to cope with the 18-month sleep regression and help your toddler get some sleep.

  • Recommit to their routine. When life gets busy, it's easy to let your toddler's routine slide. If your child is suddenly sleeping poorly, take a close look at their routine to ensure you're consistently sticking with a naptime and bedtime routine that helps get them ready for quality sleep.
  • Consider cutting a nap. If your toddler resists bedtime, they might be getting too much sleep during the day. Children usually transition from two naps to one around 18 months. If your child is still taking two naps, it may help their overall sleep to transition to just one.
  • Make bedtime relaxing. A calm routine, including dimmed lights and reading before bed, can signal your toddler that it's time to settle in for the night. By keeping the room where they sleep dark and quiet, free from screens and overstimulating toys, you can avoid distractions that might make it harder to sleep.
  • Treat symptoms. If illness (like an ear infection) or discomfort from teething is keeping your little one up at night, over-the-counter medicine may help treat the symptoms. Talk to your toddler's pediatrician if you suspect a medical issue is interfering with their sleep.
  • Have active days. Your growing toddler has a ton of energy, and keeping them active can help them sleep more soundly at night. Encourage physical play and exercise – even walking around the block can help your little one get their energy out.
  • Try sleep training. If you sleep-trained your toddler when they were younger, they may need a refresher course. And if you haven't tried sleep training yet, it's not too late! There are a few methods to teach your toddler how to fall asleep on their own: cry it out, fading, gentle, and the Ferber method.
  • Give them a lovey. If they don't have one yet, a comfort object like a blanket or stuffed animal may help your toddler soothe themself back to sleep when they wake up during the night.
  • Manage separation anxiety. Helping your toddler deal with separation anxiety during the day will improve their nighttime worries.
Follow your baby's amazing development

BabyCenter's editorial team is committed to providing the most helpful and trustworthy pregnancy and parenting information in the world. When creating and updating content, we rely on credible sources: respected health organizations, professional groups of doctors and other experts, and published studies in peer-reviewed journals. We believe you should always know the source of the information you're seeing. Learn more about our editorial and medical review policies.

Sleep Foundation. 2022. 18-Month Sleep Regression. a new window [Accessed July 2022]

Nemours Foundation. 2019. Sleep and Your 1- to 2-Year-Old. a new window [Accessed July 2022]

Children's Health. Undated. Sleep regression in infants and toddlers. a new window [Accessed July 2022]

American Academy of Pediatrics. 2018. Getting Your Baby to Sleep. a new window [Accessed July 2022]

Cleveland Clinic. 2021. When and How to Sleep Train Your Baby. a new window [Accessed July 2022]

Sleep Foundation. 2022. How Much Sleep Do Babies and Kids Need? a new window [Accessed July 2022]

Mary Sauer

Mary Sauer is a freelance parenting and health writer living in Kansas City. She is a mom of four and loves to hike with her kids, read, and knit. Cooking a complicated meal her kids probably won't eat is one of her favorite pastimes.