When should children start potty training?

The Comprehensive Guide To Potty Training Readiness:Knowing When To Start

When should parents begin the potty training process?

Parents naturally want to give their child the best start in life, and potty training is a significant milestone that parents sometimes make more stressful than necessary. A common mistake is parents starting potty training too early because a peer or a cousin of the same age has already begun, or due to pressure from relatives who insist a child should be potty trained because their child was completely trained by a certain age. It is not a race or competition to see how early one can be potty trained, there is no conclusive research that indicates there is any advantage for a child to potty train at an early age. There is no peer reviewed study or literature that shows any correlation between potty training age and intelligence, aptitude or future success.

Readiness Signs Not Age Indicates a Child is Ready To Potty Train

Age should not be a consideration when determining whether or not a child is ready for potty training. Instead, focus on the child's readiness signs which are smaller milestones or abilities that the child demonstrates and masters over time. Potty training requires several smaller milestones to be mastered in order to successfully master the more complex task of using the potty such as: fine motor skills to pull pants up and down, walking to the toilet, sitting on the toilet and communicating the need to use the toilet, among others. When a child has mastered these smaller milestones, it is indicative of their readiness to take on the more complex milestone of potty training. 

The Comprehensive Guide To Potty- Training highlights the importance of using readiness signs rather than age as the determining factor that a child is ready to start potty training. This guide compiles a comprehensive list of 21 signs from various experts, offering a broad perspective of all of the different signs appearing in different published studies, since there is no universal agreement among experts on a specific set of signs. It also provides statistics including potty training ages and time frames for reference only and to satisfy parental curiosity not to be used as goals or guidelines.

Every child is unique, and their potty training journey will reflect that. Children develop at different rates physically, mentally, and psychologically, making it impossible to assign a specific age for potty training. Parents should look for readiness signs, not age and avoid comparing their child to others. Some children may train earlier, while others may take more time, and that's perfectly okay.

The key takeaway is that there is no correlation between the age a child is potty trained and their intelligence, aptitude, or future success. By focusing on readiness rather than age, parents can make the potty training process smoother and less stressful for everyone involved.

What is the average potty training age in the US?

We emphasize again, the following statistics are for reference only and should not be considered a goal or guideline that parents consider when potty training: The average potty training age in the US is currently 37.5 months.

What is the average potty training age for girls in the US?

Girls typically train at 35 months of age. Girls generally complete potty training several months ahead of boys by an average of 4 months though this is not always the case.

What is the average potty training age for boys in the US?

Boys typically train at 39 months of age.

How long does it take for kids to potty train?

The time it takes to potty train varies greatly. It can take anywhere from a few weeks to a year or more. UC Davis reports:

"The average time to complete the potty- training process is 6 months. Most girls complete the process without accidents within a few months while boys tend to take several months longer.  The younger the child when starting potty training, the longer the process usually takes."

The problem with the statistic above is the fact that typically, children stay dry throughout the night on average about 10 months after day training is complete. As ADH (Anti- Diuretic Hormone) levels must be present at higher levels to stay dry at night, on average 10 months after the levels of ADH are ample to stay dry during the daytime.

Based upon the bodies ability to produce ADH in sufficient amounts, it reasons that on average the shortest time frame to be completely potty trained is 10 months, assuming that training started as soon as the readiness signs occurred. Unless of course it is a child that is already developed and starts potty training with ample ADH levels present for both day and night training. In that case however, the child is likely to have exhibited readiness signs for a significant period of time and potty training should have been initiated earlier.

At what age should a child be fully potty trained at night?

Since most children are trained for the day at 37 months of age, most children will be fully potty trained for the night at 47 months of age, or almost 4 years of age.

What age should a girl be fully potty trained for the night?

Since most girls are trained for the day by 35 months, they should be fully trained for the night at about 45 months or just under 4 years of age.

What age should a boy be fully potty trained for the night?

Since most boys are trained for the day by 39 months, they should be fully trained for the night at about 49 months of age or just over 4 years of age.

What is considered to be completely potty trained? Does it include being trained for the night time also?

When discussing the length of time potty training takes there is often confusion as to what entails completion of the process. Is being trained for the daytime only or both the daytime and nighttime considered being potty trained. And does it mean that there are no accidents ever or occasional accidents. If the details are not spelled out clearly on surveys, the survey results will be problematic as each person interprets individually the number of accidents permissible and whether it is potty training for the day or both night and day is necessary to constitute completion of potty training.

The survey below likely refers to children being trained for the daytime only with occasional accidents considering such a short period of time parents reported the process taking.

In a 1200 people survey of parents in the UK who have potty trained at least one child, madeformums.com revealed: the most common time period to complete potty training reported by parents was 2 to 3 weeks. However, 72% of the parents were potty training for the second or more times as only 28% were successful the first time.

When are children in other countries potty trained?

Over half of the children in nations around the world potty train by the age of one year. The age at which children are potty trained is often dictated by the parents’ socio-economic status and cultural norms. Less developed countries that lack diapers, clean water, and sanitation often start potty training shortly after birth due to necessity. Since over half of the children in the world live in under developed nations, the statistics make sense because necessity dictates these children being trained soon after birth with completion by the age of one.

Is the US behind other industrialized nations when it comes to potty training children?

While there has been dialogue suggesting that the US lags behind the rest of the world in potty training age, this is a misrepresentation. The US potty trains around the same age as the other industrialized nations in the world that have access to diapers, clean water, and sanitation, typically around three years of age. The number of children in under developed nations make up over half of the worlds population and as a result skew the average potty training age to 1 year of age. However, research from other developed nations indicates that the potty training age is very close to that of the United States.

How has the potty training age in the US changed over the years?

In the US, during the 1920s and 1930s, potty training started soon after birth and was completed by 9 months of age. However, after the war, the potty training age shifted upward to 18 months and older as experts sought to distance themselves from the often coercive and abusive practices of earlier years.

How did the advent of the disposable diaper affect the potty training age in the US?

The disposable diaper was invented in 1951 by Marian Donovan, from South Bend, Indiana, a homemaker who used a waterproof shower curtain as a cover with disposable absorptive material. This paved the way for the commercial availability of the disposable diaper.

In 1961 Pampers by Procter and Gamble became the first commercially available diaper, and mass production began. The potty training age grew from 18 to 24 months when the diaper was introduced during the 1960's.

As other manufacturers entered the market, the diaper wars began which resulted in huge marketing dollars and substantial Research & Development taking place.
The large R & D investment led to more absorbent better-fitting diapers as super absorbent polymer SAP was introduced in the 1980s. Better-fitting, drier diapers meant parents could leave children in diapers longer without the baby being uncomfortable and crying. Substantial marketing budgets were allocated for campaigns tailored to instill confidence in mothers keeping their babies in diapers longer. The diaper companies introduced diapers in bigger sizes to fit larger, older children and drive profits even higher.

As a result, during the 1980s and 1990s, the potty training age began to soar from 24 months to 36 months and beyond.

The two largest manufacturers, Procter & Gamble and Kimberly Clark, continue to dominate the diaper industry as they have for the past 50 years, with Pampers and Huggies respectively. Currently, the age is at 37.5 months with some sources insisting the age has climbed to over 42 months of age.

Which pediatricians have influenced the potty training age in the US?

  • Dr. Benjamin Spock and Dr. T. Berry Brazelton, both prominent pediatricians and child development experts, generally advocated for child-centered and individualized approaches to parenting, including potty training. Their approach and guidance emphasized understanding a child's cues, respecting individual differences, and avoiding harsh or coercive methods.
  • Dr. Benjamin Spock: Dr. Spock, in his influential book "Baby and Child Care," emphasized the importance of responding to a child's needs and understanding their unique developmental timeline. He generally encouraged a flexible and gentle approach to potty training, considering the child's readiness and temperament. While he did offer general guidelines, he believed in adapting strategies based on the child's cues and developmental progress.
  • Dr. T. Berry Brazelton: Dr. Brazelton, a pediatrician and child development specialist, authored the influential parenting book, "Infants and Mothers" that also emphasized an individualized and child-centered approach. His concept of "child-oriented toilet training" focused on understanding a child's cues and readiness signals. Dr. Brazelton's approach encouraged parents to pay attention to their child's developmental milestones and engage in a cooperative, non-coercive method of potty training that respected the child's autonomy. Dr. Brazelton's motives have been the subject of controversy however, as he appeared in commercials for Pampers as a paid spokesman advocating for parents to wait to potty train at older ages.

What are the readiness signs parents should look for to indicate a child is ready to potty train?

Parents should look for the presence of the following 21 signs to indicate a child is ready to start the potty training process. The age range indicates the approximate age the sign is likely to occur and is provided for reference only to give parents a rough idea of when a particular sign may appear. 


 Recognizing the signs of readiness for potty training in a child is crucial for a smooth and successful transition from diapers to using the toilet. Parents should be attentive to these signs and roughly aware of the age range for reference but also keep in mind that every child is unique. Not all children show the same signs or progress at the same pace. The key as previously stated is readiness signs not age should be the decisive variable as to whether to initiate potty training.

Does potty training early cause psychological damage to children later in life?

Contrary to popular beliefs, there has never been any research or studies that indicate that potty training is in any way related to the psychological well-being of children at any point during their life.

Is it bad to potty train a child too early?

The general consensus is that parents are better served to potty train early than late. However, there has been one study that has associated the following problems with early training:

  • Resistance and frustration: If a child is not developmentally ready, attempts at potty training may lead to resistance and frustration for both the child and the parents. This can create a negative association with the potty training process.
  • Incomplete bladder control: Younger children may not have developed full bladder control, leading to frequent accidents. This can be discouraging for both the child and the parents.
  • Difficulty recognizing bodily cues: Potty training too early may mean that a child has not yet developed the ability to recognize and respond to the physical cues that indicate the need to use the toilet. This can result in inconsistent success and setbacks.
  • Emotional stress: Pressuring a child to potty train before they are ready can lead to emotional stress. This stress may manifest as anxiety, fear, or a sense of failure for the child.
  • Regression: Some children who are pushed to potty train too early may experience regression, reverting to previous behaviors such as bedwetting or refusing to use the toilet.
  • Toilet training resistance: A child who is forced into toilet training before readiness may develop a resistance to the process, making it more challenging to achieve successful potty training later on.
  • Physical discomfort: Forcing a child to sit on the potty for extended periods when they are not ready can cause physical discomfort and may contribute to negative associations with the toilet.

Is it bad to potty train too late?

Most experts and research tend to agree that parents should potty train earlier rather than late. Some problems associated with late training are:
  • Urinary Tract Infections (UTIs): Prolonged use of diapers can create a warm, moist environment that is conducive to bacterial growth. This can increase the risk of UTIs, particularly in girls, due to the proximity of the urethra to the anus.
  • Constipation: Delayed potty training can sometimes lead to constipation, especially if children withhold stool due to fear or anxiety about using the toilet. Chronic constipation can contribute to bladder dysfunction and urinary retention issues.
  • Bladder Dysfunction: If a child becomes accustomed to voiding in diapers for an extended period, it might affect their ability to recognize and respond to bladder sensations. This can potentially lead to bladder control issues or urinary incontinence.
  • Delayed Bladder Maturation: Some studies suggest that delaying toilet training might lead to delayed maturation of the bladder, potentially increasing the risk of bedwetting (nocturnal enuresis) later in childhood.
  • Psychological Impact: While not strictly a physical problem, prolonged diaper use can affect a child's psychological well-being. It might hinder their sense of independence and self-esteem, which could indirectly impact their overall health and development.

Of course, late training does not guarantee problems; however, it's better to err on potty training earlier than late according to recent research.

Since no two children are alike, few generalizations can be made that hold true for all children when it comes to potty training. This is very much the case for parents looking for the ideal age to start potty training.  Parents should not consider a child's age but rather recognize the potty training readiness signs to ensure that a child is physically, mentally and emotionally ready to start the process and ensure the greatest chance of success the first time around.

What is the best age for potty training a child?

For parents who want to pinpoint the ideal age to start potty training, the ages that experts state as being ideal vary greatly from 18 to 36 months of age. Lora Jensen, author of "The 3 Day Potty Training Method" believes the ideal age to start training is 22 months of age. While other experts maintain that 28 to 30 months of age ensures a child is ready to be trained. 

After considering the different experts opinions as well as the research available. We believe that 27 months of age allows for the best chance of success potty training since control of the bladder and bowels is not complete for all children earlier than 24 months. There has been some research to indicated 27 to 32 months is the sweet spot to initiate potty training.

When should a child be fully potty trained for the night?

For a child to successfully potty train, they must be able to control their bladder and bowels. Most children do not have full control over their bladder and bowels during the daytime until 36 months of age. Control of the bladder at night time is not possible until close to 46 months or later for most children. Since night time training requires ample supply of (ADH) Anti-Diuretic Hormone to stay dry at night. The body of most children cannot produce sufficient amounts of ADH until 48 months of age.

When should a girl be fully potty trained for the night?

Most girls should be fully potty trained a few months before boys at the age of 46 months.

When should a boy be fully potty trained for the night?

Most boys should be fully potty trained at the age of 50 months. 

What is the best age to potty train a girl? What is the best age to potty train a boy?

After considering the different recommendations by the prominent experts we believe the best age is around 27 months for most children being able to recognize the sensations and having the ability to control their bowels and bladder.

If parents observe the presence of all 21 readiness signs at 27 months of age there is a great chance that successful potty training will follow. Remember stay positive, consistent and flexible at all times during this challenging endeavor and you will make it through. Good luck!

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