Methodology note
Reverse business inheritance-tax changes: calculation note
Scenario assumptions behind the Reverse business inheritance-tax changes estimate. The figures are illustrative and exclude unrelated Conservative pledges.
View main policy page: Reverse business inheritance-tax changes
Central fiscal result
+GBP 0.9bn - Net fiscal impact in 2028-29
Low case: +GBP 0.3bn. High case: +GBP 2.0bn. Positive numbers are fiscal costs or borrowing pressure. Negative numbers are Exchequer savings or receipts.
Scenario and baseline
- Model reversal of BPR restrictions by 2028-29.
- Central cost assumes a broad restoration of relief.
- Baseline is the post-2026 BPR allowance regime.
- Agricultural property relief is modelled separately.
Affected population
- Affected population is estates claiming business property relief.
- Direct beneficiaries are heirs of qualifying business assets.
- Indirect exposure includes employees, creditors and buyers of family firms.
- Passive-investment boundaries are economically important.
Gross impact
- Central cost: GBP 0.9bn annual lost IHT revenue.
- Low case assumes tight eligibility and limited planning.
- High case assumes avoidance and expanded claims.
- No firm-survival saving is booked.
Fiscal build-up, central case
- Lost inheritance-tax receipts: +GBP 0.9bn
- Compliance and anti-avoidance: GBP 0.0bn
- Higher business continuity receipts: GBP 0.0bn
- Avoidance response: GBP 0.0bn
Central net impact: +GBP 0.9bn in 2028-29.
Behaviour and pass-through
- Low case assumes active trading-business tests constrain claims.
- Central case assumes broad relief restoration.
- High case assumes wealth planning expands use of BPR.
- Business continuity gains are real but not automatically fiscal savings.
- Distributional effects are skewed to taxable estates.
Phasing
- 2026-27: +GBP 0.2bn. Preparation or partial implementation.
- 2027-28: +GBP 0.7bn. Main ramp-up year.
- 2028-29: +GBP 0.9bn. Target-year central estimate.
- 2029-30: +GBP 0.9bn. Continuation at steady-state assumptions.
Main source groups
- con-plan-2026: Conservative live policy page; used to identify current pledge wording.
- apr-bpr-2026: APR/BPR policy note; inheritance-tax relief distribution and revenue baseline.
- autumn-budget-2024: Autumn Budget baseline for tax measures Conservatives would reverse.
- hmrc-ready-2025: HMRC tax ready reckoners; main tax-cost anchor.
- mirrlees-2011: Tax design principles; informs behavioural and incidence assumptions.
- saez-slemrod-giertz-2012: Taxable-income responses; informs behavioural and incidence assumptions.