18 Month Sleep Regression
The 18 month sleep regression is often the hardest toddler regression, because it combines new independence, a second wave of separation anxiety and teething. Bedtime battles, crying when you leave and nap refusal are the classic signs. It usually lasts 2 to 6 weeks and improves with calm, consistent limits.
- Usually starts
- 17–19 months
- Typically lasts
- 2–6 weeks
- Main cause
- Independence, separation anxiety and teething
Reviewed by Pediatric sleep consultant (TBC) · Updated 2026-09-25
Check today's nap times
Next nap
12:00 pm
after 5 h awake · typical 5–6 hours
See the whole day
- 7:00 am Morning wake-up
- 12:00 pm Nap 1 · until 1:45 pm
- 7:45 pm Bedtime
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Why the 18 month sleep regression happens
- Toddlers are discovering independence and the power of "no".
- Separation anxiety can return strongly between 15 and 18 months.
- Canine teeth and molars often come through between 16 and 23 months.
- A language burst means busy minds at bedtime.
Signs of the 18 month sleep regression
- Resisting bedtime with crying, stalling or protest.
- Calling out or crying after you leave the room.
- Refusing the nap or taking a long time to fall asleep.
- Night waking or early morning waking.
If your baby also has a fever, is feeding much less, or seems unwell, it is more likely illness than a regression. Check with your pediatrician.
What helps
- Offer two simple choices in the routine (which book, which pajamas) so your toddler feels in control.
- Keep limits warm, calm and consistent. Changing the rules every night tends to make protests longer.
- Talk to your pediatrician about pain relief if teething is clearly hurting.
- Keep the nap. Almost all 18-month-olds still need one.
- Hold off on a toddler bed. Big changes during a regression often make sleep harder.
Sample day at 18 months
18 month old schedule that helps
Overtiredness makes any regression harder. At 18 months, wake windows of 5–6 hours and 1 nap a day are typical. Here is a sample day for a 7 am wake-up:
- 7:00 am Morning wake-up
- 12:00 pm Nap 1 · until 1:45 pm
- 7:45 pm Bedtime
18 Month Sleep Regression questions
How long does the 18 month sleep regression last?
Typically 2 to 6 weeks.
Why is the 18 month sleep regression so hard?
Toddlers can now protest loudly and get out of bed (or try to), and they are dealing with independence, separation anxiety and teething at once.
Should my 18 month old drop their nap?
No. Nap refusal is part of the regression. Most children need a daily nap until at least age 3.
Can teething cause the 18 month sleep regression?
It often contributes. Canines and molars arrive around this age. Check with your pediatrician about comfort options.