Private rental prices development plan, UK: updated January 2025

• We expect to complete transformation of our private rental price statistics in 2025, with the final major milestone in March 2025. 

• Private rental price statistics for Great Britain are currently produced using the Price Index of Private Rents (PIPR) methodology, while statistics for Northern Ireland continue to be produced using the Index of Private Housing Rental Prices (IPHRP). 

• From March 2025, we expect to also use PIPR methodology for Northern Ireland rents, aligning with the methodology used for Great Britain, and providing increased geographical granularity, and estimates by property type and number of bedrooms. 

• The development outlined is part of a continuous programme of improvement for consumer price statistics; utilising new data sources for further areas of the inflation basket and continuing to improve these statistics. 

• The Office for Statistics Regulation (OSR) set out several requirements in their Spotlight on Quality Assessment: Price Index of Private Rents (PIPR) report; in this release we outline our initial intentions for addressing these requirements.

• We will be discussing our intentions in more detail with the OSR and stakeholders before providing a fuller response later in 2025.

This development plan is a dynamic article that will be updated when appropriate. This update provides users with an initial understanding of the work we are planning to meet the Office for Statistics Regulation's (OSR's) quality assessment requirements. Over the coming months, we will be discussing our planned work with the OSR, and with stakeholders. This will allow us to refine, and where necessary update our plan to ensure we are sufficiently meeting each of the OSR requirements. We aim to publish this update by the end of March 2025. Changes to the plan will be announced to users through our Private Rent and House Prices bulletin.

Project aim 

In March 2024, we unified our private rental prices' statistics by replacing our Index of Private Housing Rental Prices (IPHRP) bulletin and our Private rental market summary statistics in England (PRMS) bulletin with our new monthly Private rent and house prices, UK statistical bulletin. PIPR methodology is used for Great Britain rents and IPHRP methodology continues to be used for Northern Ireland rents. 

From March 2025, we aim to also use PIPR methodology for Northern Ireland, aligning the methodology used for private rents across the UK and providing more detailed insight into the rental market for Northern Ireland. Simultaneously, in March 2025, we will also update our PIPR Quality and Methodology Information (QMI) to reflect the inclusion of Northern Ireland, and to address some of the Office for Statistics Regulation's (OSR's) quality assessment requirements.

Inflation measures 

PIPR statistics (previously IPHRP statistics) for Great Britain are used to inform the owner occupiers' housing (OOH) costs element of the Consumer Prices Index including OOH (CPIH), the Office for National Statistics (ONS)'s lead measure of consumer prices inflation, as well as "actual rentals for housing" aspect of Consumer Prices Index (CPI) and CPIH, and "rent" in the Retail Prices Index (RPI). 

Verian (previously Kantar) data continue to be used to measure Northern Ireland rents inflation in consumer prices statistics. We expect to replace Verian data with PIPR data for Northern Ireland from March 2025. More information is available in our Impact analysis on transformation of UK consumer price statistics: January 2025 article.

In 2024, we requested a quality-focused assessment of our Price Index of Private Rents (PIPR) by the Office for Statistics Regulation (OSR). This was the first step towards achieving accredited official statistics status. The OSR published their Spotlight on Quality Assessment: Price Index of Private Rents (PIPR) report in October 2024, which included some requirements for the Office for National Statistics (ONS) to address before submitting PIPR for a full assessment. The ONS' intentions for addressing these requirements are outlined in this release. 

Requirement 1: Publish more information on data collection and quality monitoring 

Requirement

The OSR requests that ONS publish a detailed account of the quality and representativeness of the private rents data that PIPR estimates are based on each month, in relation to the types of data collected where possible (agreed versus advertised) by property type and geography.   

Response

The ONS already publishes information in the PIPR QMI (and monthly statistical bulletins) relating to the types of data collected by each UK country's rent officer function, which are delivered to the ONS, and intends to publish information on typical property type and geography distributions in the March 2025 QMI update. 

Requirement

The OSR requests that ONS publish additional information on its approach to assessing the quality and representativeness of the private rents data each month, including the extent to which the rents data submitted meet expected monthly volumes. 

Response

In the March 2025 QMI update, the ONS intends to clarify further the outlier identification approach used each month, and intends to publish an annual summary of rents data collection volumes, subject to permission from the data providers. 

Requirement 2: Publish more detailed technical information on methods and source data quality 

Requirement

The OSR requests that ONS improve its communication of the quality of and uncertainty in the PIPR estimates, by including sufficiently detailed information for expert users; having shorter accessible explanations with worked examples for non-expert users; and ensuring greater consistency in the communication of important methods and quality information across the different PIPR products.  

Response

The ONS intends to update the PIPR QMI with further information on quality. Our proposed updates include presenting an illustration of the annual data volumes distribution, by country and by month, examples of annual data collection volumes (which aim to collect a proportion of all rented dwellings) by geography compared with private rental dwelling stock estimates for that area.  

The ONS intends to publish additional technical articles to meet user needs, including worked examples for non-expert users.  

Requirement

The OSR requests that ONS be clear about how the PIPR methodology works for the different source data used, including, for example, rents source data being predominantly on an advertised basis in Scotland, and completely on an advertised basis in NI. The ONS should be clear about why the same method is used even though the data sources differ.  

Response

The independent Advisory Panel for Consumer Prices Technical Panel (APCP-T) was consulted in July 2023 on the potential impact of data collection differences on rents measurement. The UK Statistics Authority's Implementation of private rental price controls in the UK paper (PDF, 447KB) was published alongside minutes for the APCP meeting on the UK Statistics Authority website. APCP-T concluded that "there was not sufficient evidence to justify a change to Index of Private Housing Rental Prices (IPHRP) methodology for Scotland" and that "due to the underlying problem with data collection for Scotland ... recommended [ONS] working with the Scottish Government to improve data collection". In the March 2025 QMI update, the ONS intends to: 

• confirm that the PIPR methodology works in the same way for each UK country, despite data collection differences 

• summarise the July 2023 APCP-T paper and independent feedback to clarify to users why the same method is used for each UK country. 

Requirement

Set out in more detail aspects of the methods choices made, including, for example, how the PIPR weights are calculated; the rationale for the data sources chosen to weight PIPR estimates; the chain-linking methods used to combine the PIPR and historical IPHRP series; and the relative strengths and limitations of these methods. 

Response

The ONS intends to set out in more detail the methods used in the compilation of PIPR, including the calculation of weights, in the March 2025 update of the QMI. This will include an assessment of the relative strengths and limitations of these methods. Further detail will also be published to provide users with a better understanding of the method used to chain -link the PIPR (from January 2015) and historical IPHRP series (before January 2015).  

Requirement

Provide a clearer rationale for choices made, for example, combining PIPR and IPHRP estimates in the presented UK totals, and clear guidance on the extent of comparability of estimates for the different UK nations. 

Response

The ONS already publishes an explanation in the monthly PIPR bulletin of how PIPR Great Britain estimates are combined with IPHRP Northern Ireland estimates to produce UK totals, and includes the Great Britain and Northern Ireland weights applied in the annual PIPR weights dataset. The ONS intends to clarify further in the bulletin how estimates are currently combined to produce UK totals. However, it is expected that from March 2025, Northern Ireland will be included within PIPR estimates. Then, from March 2025, UK totals will be produced using only PIPR-based estimates. Therefore, in the March 2025 QMI update and annual PIPR weights dataset, the ONS intends to set out clearly how UK totals will be produced from PIPR-based estimates only from March 2025. 

Requirements

Provide a fuller explanation of its approach to revising provisional UK PIPR estimates owing to NI data only becoming available two months after GB data. This should support a more transparent user understanding of the nature and extent of revisions made to PIPR estimates and make it clear that these are the only revisions made. 

Response

The revision policy currently used for UK estimates is transparently reported in ONS' monthly statistical bulletin in Section 11 "Revision Policy for Price Index of Private Rents" section. Users are also alerted to the revision policy for UK estimates in Section 2 where the UK estimates are reported, and also in the footnotes of Figure 1 and Figure 4. In the March 2025 update, the ONS intends to include the revision policy in the PIPR QMI, updating the explanation in the QMI and statistical bulletin to reflect the expected change to the production of Northern Ireland rent statistics from March 2025.  

Requirement 3: Publish a summary of user feedback received and plans for future user engagement  

Requirement

Create a strategy for engaging with a range of PIPR users. This must include how ONS plans to support users who use PIPR for housing analysis purposes. 

Response

The ONS will regularly review and update when appropriate, the Private rental prices development plan with future plans for engaging with users. The ONS is currently developing an engagement strategy for PIPR, to accompany the March 2025 QMI update and inclusion of Northern Ireland data within PIPR. It will detail how we will continue engaging with users of housing data in different government departments, and also how we will increase engagement with non-government users. The engagement strategy will consider options for supporting PIPR users, for example:  

• user feedback mechanisms 

• dedicated online forum for PIPR discussion 

• webinars and seminars 

• explainer content in different formats 

As we develop our engagement strategy, we welcome input from users on engagement methods that support their use of PIPR. Please contact us via: hpi@ons.gov.uk. 

Requirement

Create a summary of user feedback from the "in development" status of PIPR. This information should be published alongside the full UK PIPR index. 

Response ONS will update the Private rental prices development plan with a summary of user feedback and our response to this feedback. We will signpost updates to the development plan in the monthly PIPR statistical bulletin.  

Requirement 4: Clearly communicate communicate any further planned improvements and plans for evaluating PIPR's "in development" status, following Northern Ireland rents transformation 

Requirement

Clearly communicate any planned improvements that ONS intends to make in response to user feedback. Clearly communicate what user requests ONS will and will not take forward. 

Response

The ONS will update the Private rental prices development plan in 2025 with a summary of user feedback and our response to this feedback, including any planned future work. For example, some users have queried whether it would be possible to publish some additional PIPR statistics, such as breakdowns by county, or lower and upper quartile rent prices. We are assessing the feasibility of producing such metrics and will notify users of the assessment outcome in the development plan. 

Requirement

Publish plans for evaluating PIPR's "in development" status once ONS has published the full UK PIPR with NI and UK included, and for taking forward findings from its own reviews of PIPR data quality and methods. 

Response

The ONS will continue to work with the OSR to meet the requirements set out in the OSR's October 2024 report, continuing the process towards evaluating PIPR's "in development" status. The ONS will update the Private rental prices development plan in 2025, which will be the main document used to update users regarding any planned additions to PIPR outputs. The development plan will also be used to set out our ongoing engagement strategy for PIPR, user feedback summary and response to user requests. We will be exploring other forms of communication to provide users with more accessible updates, such as a blog summarising progress and next steps. 

Requirement 5: Review historic panel minutes and papers related to PIPR's development, and which may now be suitable for publication, subject to the consent of the data owners. 

Requirement

Review the historical panel minutes and papers about PIPR's development, which were previously restricted due to market sensitivity, and see if they are now suitable for publication, subject to the consent of the data owners.  

Response

The ONS will engage with the Advisory Panels for Consumer Prices to review the publication status of historical Advisory Panels for Consumer Prices documents relating to PIPR development. The ONS and APCP will re-assess the documents and engage with the data owners. Subject to gaining permission from the data owners, the ONS and the UK Statistics Authority will publish previously redacted information re-assessed as suitable for publication.

Transformed private rent prices statistics for Great Britain were introduced in March 2024, with the launch of the "Private rent and house prices, UK" bulletins. Detail of progress between 2016 and 2023 is available in our previous Private rental prices development plan article. 

Future timeline dates are estimates and subject to change. Project milestones for 2025 include:  

• publishing of the ONS' response to the OSR's recommendations, January 2025 (complete) 

• publishing an impact analysis for Northern Ireland transformation (with a related release on impact on consumer price statistics), January 2025 (complete)

• publishing decision on incorporation into official statistics, early 2025 (to start) 

• user engagement following impact analysis publication, early 2025 (to start) 

• publishing first statistical bulletin using the new PIPR methodology for Northern Ireland, March 2025 (to start) 

• regular publishing of updates on ONS' progress addressing the OSR's recommendation, 2025 (to start)