Methodology note
Restore higher bank taxes: note
Models restore higher bank taxes in 2028-29. The estimate is illustrative and excludes wider package interactions.
Central fiscal result
-£3.5bn - Net fiscal impact in 2028-29
Low case: -£5.0bn. High case: -£1.0bn. Positive numbers are fiscal costs or borrowing pressure. Negative numbers are Exchequer savings or receipts.
Scenario and baseline
- Models restore higher bank taxes by 2028-29.
- Baseline is current policy or published departmental plans.
- Central case uses published party or official anchors where available.
- Wider manifesto interactions are excluded unless stated.
Affected population
- Affected units are people, firms, households or providers depending on policy.
- Direct exposure follows the manifesto or government target group.
- Indirect exposure includes suppliers, workers, consumers and taxpayers.
- Weakest counts are widened in the low and high cases.
Gross impact
- Published anchor or scenario central is +£3.5bn in 2028-29.
- Gross costs or receipts are adjusted for behaviour and delivery risk.
- Tax, benefit or procurement offsets are separated in the fiscal build-up.
- The range is deliberately wider where implementation detail is thin.
Fiscal build-up, central case
- Gross tax or receipt yield: -£4.4bn
- Behavioural and avoidance response: +£0.7bn
- Administration and compliance cost: +£0.1bn
- Other tax-base interactions: +£0.1bn
Central net impact: -£3.5bn in 2028-29.
Behaviour and pass-through
- Low case assumes stronger delivery or receipts than central.
- Central case applies moderate behavioural leakage and pass-through.
- High case allows weaker delivery, larger take-up or higher costs.
- Output effects follow incidence, capacity and investment channels.
- Distributional gains do not automatically imply GDP gains.
Phasing
- 2026-27: -£0.4bn. Phased implementation and take-up.
- 2027-28: -£1.9bn. Phased implementation and take-up.
- 2028-29: -£3.5bn. Phased implementation and take-up.
- 2029-30: -£3.5bn. Phased implementation and take-up.
Main source groups
- Devereux, Griffith and Klemm, "Corporate Income Tax Reforms and International Tax Competition" (Economic Policy, 2002): Corporate tax changes can affect location, investment and reported profits; relevant to business and bank taxation.
- Djankov, Ganser, McLiesh, Ramalho and Shleifer, "The Effect of Corporate Taxes on Investment and Entrepreneurship" (American Economic Journal: Macroeconomics, 2010): Higher effective corporate taxes are associated with lower investment and entrepreneurship; supports caution on sector-specific corporate taxes.
- Liberal Democrats, "Funding a Fair Deal: Liberal Democrat Manifesto Costings" (2024): Party costings give 2028-29 spending, revenue and investment figures; used as starting anchors, not official costings.
- Liberal Democrats, "For a Fair Deal: Liberal Democrat Manifesto 2024" (2024): The manifesto gives announced policy detail across health, care, housing, taxes and climate; used to define the policy scenarios.