Question to the Cabinet Office:

To ask His Majesty's Government whether they plan to incorporate self-assessment income tax data into the inter-departmental business register; if so, when they expect that data to be incorporated; and what assessment they have made of the impact of including that data on the representation of sole traders and businesses operating below the VAT threshold in official economic statistics.

The information requested falls under the remit of the UK Statistics Authority.

Please see the letter below from the Permanent Secretary at the Office for National Statistics (ONS):

Lord Freyberg

House of Lords

London

SW1A 0PW

09 February 2026

Dear Lord Freyberg,

As Permanent Secretary of the Office for National Statistics (ONS), I am responding to your Parliamentary Question asking whether there is a plan to incorporate self-assessment income tax data into the Inter-Departmental Business Register; if so, when to expect that data to be incorporated; and what assessment has been made of the impact of including that data on the representation of sole traders and businesses operating below the VAT threshold in official economic statistics (HL14179).

The ONS is currently developing a new Statistical Business Register (SBR), which will replace the Inter-Departmental Business Register. We are planning to incorporate self-assessment income tax into the new SBR and are working closely with HM Revenue and Customs with the current expectation that they will be able to share the data later this year. We will then assess the data with a plan to incorporate into the SBR and assess the impact of the self-assessment data on economic statistics of businesses operating below the VAT threshold.

Yours sincerely,

Darren Tierney