Who Can Apply for a C100 Form? A Complete Guide for 2026

Fact checked by Jess Knauf, Director of Client Strategy, [15.05.2026]

If you’re wondering who can apply for a C100 form, the short answer is that parents, guardians, and certain other people connected to a child can apply as of right, while others, such as grandparents, step-parents, and wider family members, usually need permission from the court first. This guide walks you through every category of person who can submit a C100 application in England and Wales, explains the difference between applying “as of right” and applying with “leave of the court”, and shows you what each route looks like in practice.

What Is a C100 Form?

The C100 form is the official application form used in England and Wales to ask the family court to make an order about a child. It covers three main types of order under the Children Act 1989:

• Child Arrangements Order: decides where a child lives and how often they see each parent or family member.
• Specific Issue Order: resolves a specific question, such as which school a child should attend or whether they can be taken abroad.
• Prohibited Steps Order: stops a parent or another person from doing something specific, like moving the child to a new area without agreement.

Before submitting a C100, most applicants need to attend a MIAM, where a trained mediator explains your options and confirms whether mediation could resolve the matter without court.

Who Can Apply for a C100 Form as of Right?

“As of right” means you don’t need to ask the court’s permission to apply. You can fill in the C100, pay the fee, and the court will accept your application. The following people can apply as of right under section 10(4) of the Children Act 1989:

1. Parents

Both biological parents can apply for a C100. This includes:

• Mothers, who automatically have parental responsibility.
• Fathers married to the mother at the time of birth or who later married her.
• Unmarried fathers named on the birth certificate (for births registered after 1 December 2003 in England and Wales).
• Unmarried fathers not named on the birth certificate, who can still apply for a C100 even without parental responsibility, as the law treats them as parents for the purposes of applying.

2. Guardians and Special Guardians

A guardian appointed by a parent (usually in a will) or by the court, and a special guardian appointed under a Special Guardianship Order, can apply as of right.

3. Step-Parents with Parental Responsibility

A step-parent who has acquired parental responsibility, either through a Parental Responsibility Agreement signed by all those with parental responsibility, or by court order, can apply as of right.

4. Anyone Named in an Existing Child Arrangements Order

If a Child Arrangements Order is already in place and names you as someone the child lives with or spends time with, you can apply to vary, extend, or discharge that order without needing permission.

5. People the Child Has Lived With for at Least Three Years

If a child has lived with you for at least three years (the three years don’t need to be continuous but must have begun no more than five years before the application and ended no more than three months before), you can apply as of right. This often applies to long-term foster carers or relatives caring for a child informally.

6. People with Consent from All Those with Parental Responsibility

If everyone with parental responsibility for the child agrees in writing, you can apply for a C100 without needing the court’s permission.

7. Local Authority Foster Parents (in Limited Cases)

A local authority foster parent can apply as of right if the child has lived with them for at least one year immediately before the application.

Who Needs Permission (Leave) of the Court to Apply?

If you don’t fall into one of the categories above, you’ll need to ask the court for leave to apply. This is a two-stage process: you first apply for permission, and if granted, you can then make your substantive application for a Child Arrangements Order or other order.

People who typically need permission include:

• Grandparents, unless the child has lived with them for three years.
• Step-parents without parental responsibility.
• Aunts, uncles, cousins, and other relatives.
• Family friends with a close connection to the child.
• Siblings and half-siblings applying for contact with a brother or sister.
• Former partners of a parent who are not biological parents.
• Anyone else with a genuine interest in the child’s welfare.

How the Court Decides Whether to Grant Permission

Under section 10(9) of the Children Act 1989, when deciding whether to grant leave, the court must consider:

• The nature of the proposed application.
• The applicant’s connection with the child.
• Any risk that the application might disrupt the child’s life so as to harm them.
• Where the child is being looked after by a local authority, the authority’s plans for the child’s future and the wishes of the child’s parents.

The leading case on grandparents applying for leave is Re J (Leave to Issue Application for Residence Order) [2003] 1 FLR 114, which confirmed that the welfare of the child is an important consideration but is not the paramount one at the leave stage.

Comparison Table: Applying as of Right vs Needing Leave

Can Grandparents Apply for a C100 Form?

Grandparents are one of the most common groups asking who can apply for a C100 form when family relationships break down. Grandparents do not have an automatic right to apply for contact with their grandchildren in England and Wales. They must usually ask the court for leave first.

In practice, courts often grant leave to grandparents who have had a meaningful relationship with the child, particularly where contact has been stopped by one or both parents. The court will look at the closeness of the bond, the reasons contact has broken down, and whether re-establishing it would benefit the child.

“We worked with a grandmother whose contact with her two grandchildren had stopped completely after her son’s divorce. Through mediation, we helped both parents agree a regular contact pattern within six weeks, saving the family from a leave application and a contested court hearing. Mediation often resolves these situations far more quickly and far more gently than court ever could.”

— Jess Knauf, Director of Client Strategy at Mediate UK

Can Step-Parents Apply for a C100 Form?

Whether a step-parent can apply for a C100 depends on whether they have parental responsibility.

• With parental responsibility: a step-parent can apply as of right. PR is acquired by marrying or entering a civil partnership with one of the child’s parents and then either signing a Parental Responsibility Agreement with everyone else who has PR, or obtaining a court order.
• Without parental responsibility: a step-parent must apply for leave of the court before making a substantive C100 application.

If you’ve been a long-term part of a child’s life and the relationship is now at risk, mediation is often the first sensible step before considering court.

Can Other Relatives or Family Friends Apply?

Yes, aunts, uncles, cousins, adult siblings, and even close family friends can apply for a C100, but they will need permission from the court. The strongest applications tend to come from people who:

• Have had a close, ongoing relationship with the child.
• Can show that contact would benefit the child’s welfare.
• Have tried other routes first, such as mediation.
• Are not seen as a risk of disrupting the child’s settled home life.

Can Children Apply for a C100 Themselves?

A child can, in limited circumstances, apply for a C100 themselves. They must first obtain leave of the court, and the court must be satisfied that the child has sufficient understanding to make the application. This is rare and usually involves a solicitor acting for the child or representation through CAFCASS.

Do You Need to Attend a MIAM Before Applying?

Yes, in most cases. Anyone applying for a C100, whether as of right or with leave, must attend a MIAM first, unless a valid exemption applies. Exemptions include:

• Evidence of domestic abuse.
• Child protection concerns.
• Urgency, where there is a risk of significant harm or unlawful removal of the child.
• Previous attendance at a MIAM within the last four months for the same issue.

The MIAM is a single meeting with a trained family mediator who explains your options, assesses whether mediation is suitable, and can sign your C100 form to confirm you’ve attended.

Step-by-Step: How to Apply for a C100 Form

Whether you’re a parent applying as of right or a grandparent seeking leave, the process follows the same broad steps:

1. Step 1: Attend a MIAM, unless an exemption applies. The mediator will sign your C100 form.
2. Step 2: Complete the C100 form, providing details about you, the child, the other parties, and the orders you’re seeking.
3. Step 3: Add a C1A form if there are any allegations or risk of harm.
4. Step 4: Pay the court fee of £270, or apply for fee remission using form EX160 if you’re on a low income.
5. Step 5: Submit the application to the family court online or by post.
6. Step 6: Attend the First Hearing Dispute Resolution Appointment (FHDRA), usually within 4-8 weeks.

About The Author

Jess Knauf

administrator

Jess Knauf is the Director of Client Strategy at Mediate UK, Co-founder of Family Law Service and lead author at C100form.co.uk.

With over six years of experience in family mediation across England and Wales, she specialises in C100 court applications, MIAM assessments, child arrangements guidance and divorce mediation. Jess is a member of Resolution, the national organisation of 6,500 family law professionals committed to constructive resolution, and the published author of “The Complete Guide to Divorce in England and Wales 2026” available on Amazon.

She fact-checks all family law content published across C100Form.co.uk to ensure accuracy and compliance with current UK legislation.

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