Is My Child British?

What Dual National Parents Actually Need to Know

Last updated: March 2026

You’re a British citizen living abroad. You’ve got children. You’ve always assumed they’re British too. Why wouldn’t they be?

Then the new ETA rules arrive, or you try to get a passport for your child, or you move back to the UK and discover that your son or daughter is subject to immigration control — just like any other foreign national.

British nationality law does not work on assumptions. Whether your child is British depends on questions most parents have never thought about: where you were born, how you became British, whether you were married when the child was born, and when the child was born. Get the combination wrong and your child may not be British at all — even if both parents are.

This guide explains the main situations, what you can do about them, and where the real risks sit. It is not a substitute for advice on your specific facts, because nationality cases turn on details that look minor but aren’t.

The Distinction That Determines Everything

British nationality law divides citizens into two categories. The labels sound like something from a Victorian statute (because they are), but they control whether your child inherits your citizenship:

British citizen “otherwise than by descent” — You became British in your own right. Typically this means you were born in the UK to a British or settled parent, or you naturalised, or you registered as a citizen while living here. You can usually pass citizenship on to your children born abroad. They become British automatically at birth.

British citizen “by descent” — You inherited your citizenship from a parent because you were born outside the UK. This is the first generation born abroad. You are fully British, with all the same rights. But you generally cannot pass citizenship on automatically to your own children if they are also born outside the UK. This is where the problems start.

Most parents have no idea which category they fall into. If you were born in the UK, you are almost certainly British otherwise than by descent — and your children born abroad will usually be British automatically. If you were born outside the UK and inherited citizenship from your parents, you are probably British by descent — and your children born abroad are probably not British at birth.

That single distinction — where you were born — determines whether your child needs a registration application, a passport application, or something else entirely.

Scenario 1: You Were Born in the UK

If you were born in the UK and are a British citizen, your child born abroad will usually be a British citizen automatically — by descent. You do not need to register them. You can apply directly for a British passport.

This is the straightforward scenario and it covers a large number of dual national families. Your child is British from birth, by operation of law, and the passport is simply the proof of something that already exists.

But note: your child will be British by descent. That means if your child later has children of their own outside the UK, those grandchildren will not be British automatically. The citizenship passes down one generation abroad, not indefinitely. This matters more than most people think, particularly for families who have been living overseas for a long time.

The exception: if you were born in the UK after 1 January 1983, you are only automatically British if at least one of your parents was British or settled here at the time of your birth. Being born in the UK is not enough on its own for anyone born after that date. If there is any doubt about your own status, that needs to be resolved before you can be sure about your child’s.

Scenario 2: You Were Born Abroad and Are British by Descent

This is where families get caught out. You are fully British. You have a British passport. You vote, you pay tax, you consider yourself as British as anyone. But because you inherited your citizenship from a parent — rather than acquiring it in your own right — the law treats you differently when it comes to your children.

If your child is born outside the UK, they are not automatically British. They may be able to become British, but only through registration. That is an application to the Home Office, with a fee (currently over £1,000), evidence requirements, and the possibility of refusal.

There are two main registration routes:

Route A: Section 3(5) — Family Living in the UK

If your family has moved to the UK (or a qualifying British overseas territory), your child may be entitled to register as British under section 3(5) of the British Nationality Act 1981. The key idea is that the child, the British‑by‑descent parent, and (usually) the other parent have actually been living here for a few years before you apply.

The requirements, in broad terms, are:

The child was born outside the UK to a parent who is British by descent.
The child and both parents have lived in the UK together for a continuous period of three years ending on the date the Home Office receives the application (or in a qualifying British overseas territory instead of the UK).
The child, and both parents, were physically in the UK at the start of that three‑year period.
Neither the child nor either parent has been absent from the UK for more than 270 days in total during those three years (and there is no discretion to ignore extra absences).
The child is under 18 on the date of application and, if aged 10 or over, meets the “good character” requirement.
Both parents consent to the application, unless the law allows one parent’s consent to be enough because of death, separation or similar reasons.

The crucial advantage of this route is that a child registered under section 3(5) becomes British otherwise than by descent. That means they can pass citizenship on automatically to their own children born abroad, breaking the one‑generation‑abroad limit.

Route B: Section 3(2) — Grandparent Connection

If the family is still living abroad, there may be a route through a UK‑born (or otherwise than by descent) grandparent under section 3(2). This looks at the British‑by‑descent parent’s links to the UK before the child was born.

Under section 3(2), a child born abroad can have an entitlement to register as British if:

The child was born outside the UK on or after 1 January 1983.
One parent (the “parent in question”) was a British citizen by descent at the time of the child’s birth.
The child’s grandparent (that parent’s mother or father) became, or would but for their death have become, a British citizen otherwise than by descent — either on 1 January 1983 or at the time of the parent’s own birth.
The British‑by‑descent parent lived in the UK for a continuous period of three years at any time before the child was born, was physically present in the UK at the start of that period, and was not absent for more than 270 days in total during those three years.
Both parents consent to the application, unless an exception applies.

A child registered under section 3(2) becomes British by descent. The generational limitation therefore continues: if that child later has their own children abroad, those children will not normally be British automatically.

Scenario 3: The Second Generation Abroad — The Real Trap

Here is where the system catches families completely off guard.

Imagine: your parent was born in the UK (British otherwise than by descent). You were born abroad (British by descent). You have a British passport. Your child is born abroad too. Your child is not British at birth. If the conditions for registration under section 3(2) or 3(5) are not met — perhaps because the parent never lived in the UK for three years, or because the grandparent’s status doesn’t quite fit — then the child has no entitlement to register.

The child may still be able to register at the Home Secretary’s discretion under section 3(1), but discretion means exactly that: there is no guarantee. The Home Office will look at the child’s connections to the UK, whether the family intends to live here, and whether registration would be in the child’s best interests. These applications need to be carefully prepared.

This scenario is more common than you’d think. British families who emigrated a generation or two ago — to Australia, Canada, South Africa, the Gulf states — often discover that their grandchildren have no claim to citizenship at all, despite the family considering itself thoroughly British. The new ETA rules are making this visible for the first time, because the child now needs an ETA or visa to visit the UK.

The Unmarried Father Problem

British nationality law has a long and uncomfortable history with unmarried fathers. Until 1 July 2006, a child could only acquire British citizenship automatically through their father if the parents were married. An unmarried British father could not pass on his citizenship to his child, even if he was named on the birth certificate and had always been part of the child’s life.

This was eventually recognised as unfair, and Parliament introduced provisions to allow registration for people affected:

Section 4F allows a person born before 1 July 2006 to an unmarried British father to register as British, provided there is evidence of paternity and the father was British at the time of birth.
Section 4G covers people who would have been entitled to register under another provision (like section 3(2) or 3(5)) if their parents had been married.
Section 4L is a broader provision for anyone who missed out on citizenship due to “historical legislative unfairness, an act or omission of a public authority, or exceptional circumstances.” This is the safety net, but it requires a carefully argued application.

These provisions exist because the law was wrong, and they matter enormously to the people affected. But the applications are not straightforward. You need to show what would have happened if the law had been different — which means understanding the alternative legal pathway and building the evidence to support it. This is specialist work.

Children Born in the UK to Non-British Parents

This is the other side of the coin. If your child was born in the UK but neither parent was British or settled at the time, your child is not automatically British. Birth in the UK has not been enough on its own since 1 January 1983.

However, the child can become British if:

A parent becomes settled or British while the child is still under 18. The child can then register under section 1(3) of the British Nationality Act 1981.
The child lives in the UK for the first ten years of their life without being absent for more than 90 days in any of those years. They can then register under section 1(4). If the child is over 10, a good character requirement also applies.

For families where the parents are on a route to settlement — for example, on a spouse visa or a skilled worker visa — the timing of the child’s registration application matters. If you are planning to apply for ILR, consider whether it is worth registering the child at the same time, because the parent’s settlement may unlock the child’s right to register.

What the New ETA Rules Have Changed

The ETA system that took effect in February 2026 has not changed nationality law. It has not made anyone more or less British. What it has done is make the consequences of unresolved nationality status visible in a way they never were before.

Previously, a family could muddle through. A child without a British passport could travel on their other nationality, produce some documents at the border, and usually get in. The ETA system has closed that gap. Airlines now check nationality status electronically before boarding, and if the system does not recognise your child as British, the airline will not let them fly — or will require an ETA, which is not designed for people who are actually British.

If you have been putting off sorting your child’s nationality status, the new rules have turned “I’ll deal with it later” into “I need to deal with it before we book flights.”

Practical Steps

Step 1: Work out your own status. Are you British otherwise than by descent, or British by descent? If you were born in the UK, you are almost certainly the former. If you were born abroad and inherited citizenship from a parent, you are probably the latter. If you are not sure, check before doing anything else — your child’s entitlement depends on yours.

Step 2: Check whether your child is automatically British. If you are British otherwise than by descent and your child was born abroad, they are almost certainly British automatically. Apply for their passport. If you are British by descent and your child was born abroad, your child is not automatically British. You need to consider registration.

Step 3: If registration is needed, identify the right route. Section 3(5) is preferable to section 3(2) because it gives the child a stronger form of citizenship. But it requires the family to have lived in the UK. Section 3(2) can work from abroad but depends on the grandparent’s status. If neither fits, discretionary registration under section 3(1) may be possible but is not guaranteed.

Step 4: Do not assume it is simple. The registration fee is over £1,000 and is not refunded if the application fails. The application form (MN1) is long and technical. Getting it wrong wastes money and, more importantly, time — particularly if the child is approaching 18, after which the registration routes close and they must apply as an adult through naturalisation instead.

When You Need Advice

If you are British otherwise than by descent and your child was born abroad, you probably do not need a lawyer. Apply for the passport.

You should take advice if:

You are British by descent and your child was born abroad
You are not sure whether you are British by descent or otherwise than by descent
The child’s parents were not married at the time of the birth (particularly if the child was born before July 2006)
The child is approaching 18 and has not been registered
A previous application has been refused
The child was born in the UK but is not British because neither parent was settled at the time
You think there may be a claim based on historical unfairness (sections 4F, 4G, or 4L)

We advise on complex nationality and registration cases, including where the route is unclear or where discretion needs to be exercised. A short, focused conversation is almost always cheaper than a refused application.

Not sure whether your child is British? We can review your family’s nationality position and tell you clearly what the options are. Book a free 15-minute consultation. No obligation. No pressure.

This guide explains how the law generally applies. It is not a substitute for advice on your specific facts. Nationality law is technical, and small differences in circumstances can produce very different outcomes. If you are unsure about your child’s status, take advice before making an application.