Learn how to file a C100 form with this simple step-by-step guide. Find out what information you need, how to submit your application, and what happens next.

If you and your child’s other parent cannot agree on important decisions, you may need help from the family court. This can feel stressful, especially if you have never dealt with legal paperwork before.

The good news is that filing a C100 form is much easier when you know what to expect. You do not have to be a legal expert to complete the process. You simply need to understand the steps and provide accurate information.

Whether you are asking the court to decide where your child should live or how often they should spend time with each parent, this guide will walk you through how to file a C100 form in plain English.

If you are looking for more information about the C100 Form, understanding the process before you begin can help you avoid delays and common mistakes.

What Is a C100 Form?

A C100 form is a court application used in England and Wales when parents or guardians cannot agree on arrangements for a child.

You can use it to ask the family court to make decisions about:

• Where a child will live
• When a child spends time with each parent
• Holiday arrangements
• School-related decisions
• Other important issues affecting the child’s welfare

The court’s main concern is always the child’s best interests.

When Should You File a C100 Form?

You should only file a C100 form after trying to resolve the disagreement outside court, unless your situation qualifies for an exemption.

Many parents reach an agreement through:

• Family discussions
• Solicitors
• Mediation

If these options do not work, or there are safety concerns such as domestic abuse, the family court may become necessary.

Step 1: Decide Whether You Need Mediation

Before filing a C100 form, most applicants are expected to attend a Mediation Information and Assessment Meeting (MIAM).

A MIAM helps parents explore whether mediation could resolve the dispute without going to court.

However, you may not need a MIAM if:

• There has been domestic abuse.
• The application is urgent.
• There are child protection concerns.
• Certain other legal exemptions apply.

You should only claim an exemption if it genuinely applies to your circumstances.

The UK Government explains the mediation requirement and exemptions in detail on its official guidance.

Step 2: Gather the Information You Need

Before you begin completing the form, collect all the important details.

This usually includes:

• Your full name and address
• The other parent’s details
• Your child’s information
• Details of anyone with parental responsibility
• Information about previous court cases, if any
• Details of any safety concerns

Having everything ready before you start makes completing the application much easier.

Step 3: Complete the C100 Form

Now it is time to fill out the application.

The form asks questions about:

• You
• Your child
• The other parent
• The type of court order you want
• Why you are making the application
• Whether mediation has taken place
• Any welfare concerns

Take your time.

There is no prize for finishing quickly.

The court would rather receive a complete and accurate form than one that has been rushed.

Step 4: Explain Your Situation Clearly

One of the most important parts of the application is explaining why you are asking the court for help.

Keep your explanation:

• Honest
• Clear
• Focused on your child

For example, instead of saying:

“My ex is impossible.”

You could write:

“We have been unable to agree on weekly contact arrangements despite several discussions.”

This gives the court useful information without sounding emotional.

Step 5: Include Any Safety Concerns

If you believe your child is at risk or there has been domestic abuse, you should include that information.

The form gives you the opportunity to explain concerns involving:

• Domestic abuse
• Child abuse
• Threats
• Harassment
• Violence
• Other safeguarding issues

If possible, include facts, dates, and supporting information rather than opinions.

The court takes safeguarding concerns seriously.

Step 6: Review Everything Carefully

Before submitting the application, read through every page.

Check that:

• Names are correct.
• Dates are accurate.
• Addresses are complete.
• Questions have been answered.
• You have signed where required.

A few extra minutes reviewing the form can save weeks of delays later.

Step 7: Submit Your Application

Once the form is complete, you can submit it to the family court.

You can usually apply online or send your application by post, depending on your circumstances.

There is normally a court application fee, although some people qualify for financial help through the Help with Fees scheme.

What Happens After You File the C100 Form?

Many parents think the process ends once they submit the paperwork.

In reality, it is only the beginning.

After your application is received, the court starts preparing your case.

The next stages usually include:

• The court checks your application.
• CAFCASS carries out safeguarding checks.
• Both parents may be contacted.
• A first hearing is arranged.

The exact process depends on your family’s circumstances.

What Does CAFCASS Do?

CAFCASS stands for the Children and Family Court Advisory and Support Service.

Their job is not to take sides.

Instead, they help the court understand what is best for the child.

They may:

• Speak with both parents
• Carry out police and social services checks
• Identify any safeguarding concerns
• Share information with the judge

Their involvement helps the court make informed decisions.

More information about their role is available from CAFCASS.

How Long Does It Take?

Every case is different.

Simple cases where parents quickly reach an agreement may finish within a few months.

More complicated cases often take longer if:

• There are safeguarding concerns.
• Parents strongly disagree.
• Additional evidence is required.
• Several hearings are needed.

Unfortunately, court schedules can also affect how quickly a case moves.

Common Mistakes to Avoid

Filing a C100 form is straightforward, but small mistakes can slow things down.

Here are some of the most common ones.

Leaving Questions Blank

Answer every question that applies to you.

Missing information may delay your application.

Writing Emotion Instead of Facts

The court wants evidence and clear explanations.

Avoid using insults or personal attacks.

Stay calm and focus on what has happened.

Forgetting Supporting Information

If the court needs important details to understand your case, include them from the beginning.

That helps avoid unnecessary requests later.

Not Checking the Form

Simple spelling mistakes, incorrect addresses, or missing signatures can create avoidable delays.

Always review everything before submitting it.

Tips for Filing a Strong Application

You do not need to write like a lawyer.

In fact, simple language is often the best approach.

Keep these tips in mind:

• Be honest throughout the form.
• Stick to facts.
• Focus on your child’s needs.
• Use dates whenever possible.
• Keep copies of everything you submit.
• Follow any instructions from the court promptly.

The clearer your application is, the easier it is for the court to understand your situation.

Stay Focused on Your Child

It is easy to become frustrated during disagreements between parents.

However, the family court is not there to decide who is the better parent.

Its job is to make decisions that support the child’s welfare.

As you complete your application, try to keep every answer centred on what is best for your child.

That approach often leads to a stronger and more helpful application.

Final Thoughts

Learning how to file a C100 form may seem overwhelming at first, but the process becomes much more manageable when you break it into simple steps.

Start by understanding whether you need mediation, gather the information required, complete the form carefully, and review everything before submitting your application. Once your case reaches the court, follow each instruction and continue to focus on your child’s best interests.

While every family’s situation is different, taking your time and providing accurate information can help your application move through the process more smoothly. A well-prepared C100 form gives the court the information it needs to make informed decisions that support your child’s future.