White British fertility has fallen to 1.31 — lower than any demographic model assumed

Every ethnic demographic model in use today overestimates White British fertility.

ONS Linked Births 2024 — 567,460 births with ethnicity recorded — gives us the first opportunity to compute empirical fertility rates by ethnic group from recent official data. The results challenge the assumptions baked into every published projection.

White British TFR: 1.31. Academic models use 1.55 (Coleman and Dubuc, 2010; Rees et al., 2012). Census 2021 child-woman ratios imply 1.71. The actual rate in 2024 is 1.31 — below replacement (2.1) and below any assumption currently in use. 304,244 births to White British mothers from a female population aged 15-44 of approximately 6.97 million.

Pakistani TFR: 2.52. This is higher than the Census CWR-implied 2.15 and close to the old academic assumption of 2.45. Pakistani fertility has not converged toward the national average as some models assume.

The gap between the two is the real story:

• Pakistani to White British ratio: 1.92× (each Pakistani woman has nearly twice as many children)
• Black African to White British: 1.85×
• Other Asian to White British: 2.00×
• Indian to White British: 1.66×
• Black Caribbean to White British: 0.86× (lower than WBI)

What this means for projections: The current HP model uses Census 2021 child-woman ratios, which are based on 2016-2021 births (children aged 0-4 in 2021). The 2024 ONS data shows fertility has fallen further since then, particularly for White British. This means our current projections may slightly understate the pace of diversification — WBI births are falling faster than the model’s CWR-based fertility implies.

Methodology: Empirical TFR ≈ (annual births by ethnicity) / (female population aged 15-44 by ethnicity) × 30. Female population denominators from Census 2021 custom dataset. This is a simplified computation — precise TFRs require age-specific rates. ONS births data includes age of mother, enabling precise ASFR computation in future model updates.