UKMOD B2026.05 released

UKMOD version B2026.05 is now available, with updates to the Autumn 2026 Budget statement and other improvements.

Budget Statement 2026

  • Household Energy Payment provides a one-off £100 payment per eligible primary residence in Council Tax Bands A, B, C or D in January 2027 (2026/27 policy year).
  • Support for Energy Bills: Cut VAT on domestic electricity from 5% to 0% from 1 October 2026 to 1 July 2027
  • Fuel Duty: Extend the temporary 5p-per-litre duty cut1 and defer the planned Retail Prices Index (RPI) increase to 1 July 2027 – both the 5p-per-litre cut and RPI uprating will now occur all at once on 1 July 2027, raising duty from 52.95p to 60.59p per litre.
  • Parental Pay: Parental Allowance for fathers, partners and adopters introduced in Great Britain from April 2029. Modelled on the Maternity Allowance.
  • Pension Tax Allowance: Introduced into the model to remove the income tax liability for pensioners with total income up to the value of the new State Pension from 6 April 2027 until 5 April 2030.
  • Property Income: Increase tax rates on property income by 2ppts at the basic, higher and additional rate from 6 April 2027 (basic rate in 2027 will now be 24%)
  • Savings Income: Increase tax rates on savings income by 2ppts at the basic, higher and additional rate from 6 April 2027(basic rate in 2027 will now be 24%)

Policy Additions

  • A new system has been added to the model for 2031/32, aligning to OBR projections.
  • Added option to simulate devolved taxes on property income in Scotland separately from non-saving non-dividend income.

Data Revisions

  • All uprating indices updated, including those based on statistics reported by the OBR in the October 2026 edition of the Economic and Fiscal Outlook.
  • UK_2024_d2 data have now been released.

Code Corrections and Amendments

  • Corrected bug in application of consumer prices (4.24) and added revised adjustment parameters to match indirect taxes to NA aggregates.
  • Bug corrected for the UK_2018 system which saw the independent child element of the Child Tax Credit counted twice – once for the newly introduced two child limit and another for the legacy policy context.
  • Updated forward projections for basic rates of UC to reflect legislation (https://www.legislation.gov.uk/ukpga/2025/22).
  • Amended coding of Winter Fuel Allowance (Winter Heating Payment) to better reflect eligibility conditions of scheme as described https://www.gov.uk/winter-fuel-payment/how-much-youll-get. The coding update increases simulated WFA payments by £380 million in 2026 (from £1.3Bn to £1.7Bn), and simulated caseloads by just under 3 million people (from 7 to 9.9 million).
  • Amended code for Limited Capability for Work-Related Activity to define explicitly the lower rates payable to new claimants. LCWRA parameters also updated to reflect rates published for 2026/27.
  • Income taxes projected by policy tin_uk have been completely revised to improve clarity, resulting in the following substantive adjustments:
    • Starter rate for savings taxes amended
    • Excess of personal allowance to non-dividend income deducted from dividend income
    • Property income taxation revised from last income source – income sources for tax purposes now organised as described in Change to tax rates for property, savings and dividend income — technical note – GOV.UK

The model is available for download from the CeMPA website at https://www.microsimulation.ac.uk/ukmod/access.