The IB landscape in London
The traditional UK independent sector heavily favours A-Level. Where IB Diploma exists in London independents it tends to be offered alongside A-Level for globally-mobile or non-UK destination-bound students. The strongest IB pathways in London therefore concentrate in the pure international schools (ACS, Southbank, ICS, ASL) plus a small group of independents that have committed seriously to IB (King's College Wimbledon, Whitgift, JAGS, Mill Hill).
The 2026 top 8 IB schools in London
King's College School Wimbledon
One of the strongest IB Diploma cohorts globally. Three-year average above 40 points. Selective, academically powerful, deep faculty. Strong destinations to Oxbridge, top US universities and elite global universities. The default first choice for academically strong London families wanting IB.
Sevenoaks School (Kent, accessible from London)
The UK's most committed IB school. IB-only since 2007. Three-year average around 39 points. Strong day and boarding cohorts. Accessible to south-east London families. Particularly suited to academically ambitious families willing to commute or board.
ACS International (Cobham, Egham, Hillingdon)
Three campuses around outer London. Full IB continuum, particularly suited to internationally mobile American and global families. Strong sixth-form across all three sites. Hillingdon (closest to Heathrow) skews most toward US-bound families; Cobham and Egham have more diverse cohorts.
Southbank International School
One of the longest-established IB-only international schools in London. Two campuses (Hampstead for primary, Westminster for secondary). Smaller cohort sizes than ACS but strong academic outcomes. Particularly suited to globally-mobile families with shorter London time horizons.
International Community School (ICS) London
Central London IB-only school. Small and personalised. Strong sense of community. Smaller sixth-form means narrower subject choice but more individual attention. Worth shortlisting for families wanting central location and IB.
Whitgift School
Boys' school running both IB and A-Level. Strong IB cohort. Particularly notable for excellent music and sport programmes alongside academic outcomes. South London setting; broader catchment than the central international schools.
JAGS (James Allen's Girls' School)
Girls' school running IB Diploma alongside A-Level. Strong IB cohort. Highly selective. Excellent destinations to Oxbridge and top US universities. South London catchment. The strongest dual-pathway girls' school in London.
American School in London (ASL)
The premier American international school in London. Most students take AP rather than IB; the IB cohort is smaller but credible. Strong US university counselling and destinations. Best for American families wanting US-style high school in London with IB option.
What didn't make the list
Several London schools offer IB Diploma but with smaller cohorts or insufficient outcomes data to rank reliably. Mill Hill School, Marymount London (girls') and a handful of others would deserve consideration on a longer list.
IB vs. A-Level in London
For most UK-domiciled families heading to UK universities, A-Level remains the dominant and arguably preferred choice. particularly at top of the academic distribution and for STEM. IB Diploma gains the edge for globally-mobile families, those targeting US and continental European universities, and those who value the breadth of TOK, EE and CAS components. Read our deeper analysis in the IB vs. British curriculum guide.
Fee context
IB Diploma at the top London independents costs GBP 33,000-44,000 per year (post-VAT). At the international schools (ACS, Southbank, ICS, ASL) GBP 28,000-38,000. See our full London school fees report for the post-VAT picture.