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British citizenship through a grandparent
Enter the child's age and whether the British parent lived in the UK for 3 years before the birth: the tool says whether form MN1 applies.
Can the child be registered on form MN1?
Section 3(2) residence not met
Section 3(5) only
| Route | Section 3(5): family living in the UK for 3 years |
| Home Office fee | £1,000 |
| Child becomes | British otherwise than by descent, under s. 3(5) |
Apply before the 18th birthday; the Home Office usually decides within 6 months.
British citizenship by descent through a grandparent is the question most Americans with an English or Scottish grandmother ask, and the answer depends on age. For an adult, a grandparent born in the UK opens no route as of right: citizenship passes automatically one generation abroad, so your parent was British but you are not. For a child under 18, section 3(2) of the 1981 Act allows registration, sometimes called double descent, if the parent who is British by descent lived in the UK for 3 years in a row at some point before the child's birth, with no more than 270 days away. The application is made on form MN1, costs £1,000 and must be filed before the 18th birthday. The child then becomes British by descent. The UK Ancestry visa is a different thing: a work visa open only to Commonwealth citizens, not to someone who holds US citizenship alone.
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Why the grandparent alone does not pass it on
Section 2 of the 1981 Act gives citizenship by descent to a child born abroad when a parent is British "otherwise than by descent", which means born, adopted, naturalized or registered in the UK. Your parent, born in the United States to a British-born grandparent, received citizenship by descent under that rule. A citizen by descent does not pass it on automatically. So the chain stops one step before you, whatever the strength of the family ties.
| Who | Age | Route | Fee |
|---|---|---|---|
| Grandchild | Under 18 | Section 3(2), parent lived 3 years in the UK before the birth | £1,000 |
| Grandchild | Under 18 | Section 3(5), child and parents living in the UK for 3 years now | £1,000 |
| Grandchild | 18 or over | No route as of right | Not applicable |
The section 3(2) conditions
The form MN1 guidance sets three conditions. The child was born abroad to a parent who is a British citizen by descent. That parent's own parent, your child's grandparent, was British otherwise than by descent when the parent was born. And the British parent lived in the UK for a continuous period of 3 years at any time before the child's birth, with absences of no more than 270 days. The application must be made while the child is under 18. A child aged 10 or over must also be of good character.
A typical American case: a grandfather born in Leeds, a mother born in Boston who is British by descent and spent three years in the UK after college, and a daughter born in Boston afterwards. The daughter can be registered. Had the mother's three years come after the daughter's birth, they would not count for that child.
A child registered this way becomes a British citizen by descent, not otherwise than by descent. That means the child, in turn, will not pass citizenship automatically to their own children born outside the UK.
Can the child be registered on form MN1?
Section 3(2) residence not met
Section 3(5) only
| Route | Section 3(5): family living in the UK for 3 years |
| Home Office fee | £1,000 |
| Child becomes | British otherwise than by descent, under s. 3(5) |
Apply before the 18th birthday; the Home Office usually decides within 6 months.
Section 3(5): moving to the UK as a family
When the parent never lived in the UK before the birth, section 3(5) offers another door, but it requires a move. The child and both parents must have lived in the UK for the 3 years ending on the date of application, with no more than 270 days of absence each, and the Home Office has no discretion to overlook longer absences. If the parents have separated, only the child and one parent need to meet the residence test. A child registered under section 3(5) becomes British otherwise than by descent. Section 3(1) also lets the Home Secretary register any child at discretion when there are compelling reasons.
Fee, time and ceremony
The fee table sets £1,000 for registering a child under 18, with an extra £130 if the child turns 18 during the process and must then attend a ceremony. The Home Office usually decides within 6 months. A child under 18 becomes British on the date the application is approved, with no ceremony required, and can then apply for a British passport.
The Ancestry visa is not citizenship
The UK Ancestry visa is often confused with citizenship by descent. It lets a person with a grandparent born in the UK live and work there for a period, and it is open only to Commonwealth citizens and certain British nationals. A person who is only a US citizen cannot apply. Adults with no registration route are left with ordinary immigration routes and, after years of residence, naturalization. The British citizenship by descent page covers adults whose own parent was born in the UK, the second passport guide compares other European routes, and the family tree checker tests every branch at once.