C1A — Supplemental Information Form (Allegations of Harm and Domestic Violence)
Filed alongside C100 where there are allegations of domestic abuse, harm to the child, or risk of harm. Provides the court with full details of the allegations.
Who uses this form
Applicants completing a C100 where they need to disclose domestic abuse, harm to the child, parental alienation, substance misuse, or any other safeguarding concern.
When to use it
Always file C1A alongside C100 if any safeguarding concern exists. The court will conduct a safeguarding check and may list a FHDRA (First Hearing Dispute Resolution Appointment) with Cafcass input.
Where to file
Filed together with the C100 at the Family Court.
Court fee
Free — filed as part of the C100 application.
Common mistakes to avoid
Not filing C1A when there are genuine safeguarding concerns — the court may adjourn the case to obtain the information
Providing insufficient detail — vague allegations are less likely to trigger appropriate safeguarding steps
Including allegations that are not relevant to the child's welfare — focus on impact on the child
Not keeping a copy of the completed form
Related Guides
Related Letter Templates
Official source
Download / view form on GOV.UK or HMCTSAlways download forms directly from official government sources. Third-party copies may be outdated.