At what age are children typically potty trained during the day and at night?

Typical Ages for Daytime and Nighttime Potty Training

Most children achieve daytime urinary continence by age 4 years and nighttime continence between ages 5-7 years, though full nighttime dryness may not occur until the second decade of life in some children. 1

Daytime Continence Timeline

• Voluntary sphincter control typically develops by age 3 years, which is the critical milestone for beginning toilet training 1
• Daytime bladder control is usually achieved before nighttime control, following bowel control during sleep and daytime bowel control 1
• Girls typically achieve continence milestones earlier than boys across all domains 1
• Most children in the United States begin toilet training between 21-36 months of age, with training typically starting around age 3.4 years and completing by age 6.6 years in typical development 2, 3

Nighttime Continence Timeline

Nighttime dryness takes significantly longer to achieve than daytime control:

• 12-25% of 4-year-olds still experience nocturnal incontinence 1
• 7-10% of 7-8-year-olds continue to wet the bed 1, 4
• 2-3% of 12-year-olds still have nocturnal enuresis 1
• 1-3% of teenagers may continue bed-wetting into late teenage years 1

The spontaneous cure rate is approximately 14-16% annually after age 4 years, meaning many children naturally outgrow nighttime wetting over time 1

When to Consider Clinical Intervention

Enuresis becomes a clinical concern after age 4-5 years for daytime accidents and after age 5-6 years for nighttime wetting:

• Before age 4-5 years, bed-wetting is considered a normal developmental variant unless specific medical causes are identified 1
• The International Children's Continence Society recommends that active treatment for nocturnal enuresis should usually not be started before age 6 years 1
• Enuresis is formally defined as urinary incontinence occurring at night during sleep in children 5 years or older for 3 consecutive months 4

Special Populations with Delayed Continence

Certain conditions result in significantly delayed toilet training:

• Children with Williams Syndrome typically achieve daytime continence by age 4 years, but only 50% achieve nocturnal continence by age 10 years 1
• Children with nephrogenic diabetes insipidus may not achieve full nighttime continence until the second decade of life due to large urine volumes, with median nighttime continence at 8-11 years 1
• Children with Down Syndrome in one study completed toilet training at an average of 6.6 years, with a linear trend showing only 52.9% fully trained by ages 13-17 years 3

Key Developmental Sequence

The consistent sequence of continence achievement is 1:

1. Bowel control during sleep (first milestone)
2. Bladder and bowel control during wakefulness (second milestone)
3. Bladder control at night (final milestone, often taking years longer)