Palace of Westminster restoration: £3bn initial phase to launch underground and enabling works

Parliament’s Restoration and Renewal (R&R) Client Board has published costed proposals for the long-delayed restoration of the Palace of Westminster, recommending a £3bn, seven-year first phase of works to begin as early as 2026, subject to approval by both Houses.

The Grade I-listed complex, largely dating from the Victorian era, has experienced sustained deterioration of its fabric and building services. According to the board, Parliament is now “beyond the point where putting off these major works is sustainable”. Maintenance costs currently stand at approximately £1.5m per week, with a 70% increase in maintenance jobs recorded between 2021 and 2024. Since 2016, there have been 36 fire incidents, 12 asbestos incidents and 19 stonemasonry incidents across the estate.

The proposed phase one programme would include the construction of temporary chambers and office space to facilitate future moves, refurbishment of Victoria Tower, preparatory works to the medieval Cloister Court, commencement of underground construction, and construction of a river jetty on the Thames to support logistics. The works are capped at £3bn and intended to build momentum for the wider programme.

Alongside phase one, long-term delivery options have been reduced to two. A “full decant”, relocating both Houses from the Palace, is estimated to cost up to £15.6bn and take 19–25 years. A staged or semi-decant option could extend to 38–61 years, with projected costs approaching £39–40bn. A final decision between these models is not expected before 2030.

Deep-ground investigations of the River Thames and the River Terrace were undertaken in 2025 to inform future construction phases. Parliamentary approval of phase one will determine whether enabling works proceed while broader restoration governance and delivery structures are finalised.