Portsmouth files HMO conversions at 11 times the national rate. The rental city rebuilds itself from within.
Portsmouth City Council received 1,084 planning applications in 2025. Of those decided, 87.8% were approved, broadly in line with the national rate. The real story is the application mix: HMO conversions made up 13.6% of all applications, against 1.2% nationally, a multiple of 11 times. One in 14 applications was retrospective, built before permission was sought, at 1.9 times the national share. This is the planning profile of a dense, island city remoulding its housing stock for shared living.
The year in one line
Portsmouth filed HMO conversions at 11 times the national rate and retrospective applications at 1.9 times, the signature of a dense island city converting its housing stock for shared and rented living.
What Portsmouth Is Building
Extensions lead, but HMO conversions set the city apart.
Home extensions were the most common application type submitted to Portsmouth Council in 2025, at 23.5% of all applications. That is below the national share of 29.1%. The defining figure is HMO conversions: 13.6% of applications, against a national average of just 1.2%. Change of use to residential added a further 7.3%, and retrospective applications 7.1%. This is the mix of a dense island city steadily converting its housing stock for shared and rented living.
Applications submitted to Portsmouth Council in 2025, by project type (2024-2025 pooled counts shown).
The HMO effect
Portsmouth files HMO conversions at 11.1 times the national share and change of use to residential at 3.3 times. In a tightly packed island city with strong rental demand, converting houses into shared lets is the defining feature of the application mix.
The council verdict
Approval in line with the nation.
Of the 1,888 applications decided across 2024-2025, 87.8% were approved and 12.2% refused, broadly matching the national rates of 87.6% approved and 12.4% refused. Portsmouth's planning story is not about a hard refusal regime but about what people are applying for: HMO conversions and retrospective works at multiples well above the national norm.
About 1 in 8 Portsmouth applications does not get approved.
of decided applications were refused, broadly in line with the 12.4% national rate. About 1 in 8 applications does not get approved.
Portsmouth vs The National Norm
A city converting itself, by the numbers.
Set Portsmouth's application mix against the national average and the HMO story dominates. HMO conversions appear in 13.6% of applications here, against 1.2% nationally, 11.1 times the norm. Change of use to residential runs at 3.3 times the national share, and retrospective applications at 1.9 times. Home extensions, the most common project type, are actually below the national share. Demolition is also well below the national rate, unsurprising in a dense island city where little space is left to knock down and start again.
Portsmouth files HMO conversions at more than eleven times the national rate. In a dense island city with strong rental demand, converting houses into shared lets shapes the entire application mix.
Each bar is Portsmouth's share of applications; the marker is the national share. HMO conversions are the city's defining outlier.
Meanwhile, the market
Prices rose alongside the building work.
Permission may be straightforward to win here by national standards, but demand remains strong: the average Portsmouth home climbed over the year even as one in eight applications was turned down.
Portsmouth's planning data tells the story of a city under pressure to house more people in less space. The HMO conversion rate, at more than eleven times the national share, shows how much of the existing stock is being adapted for shared living. One in fourteen applications is retrospective, work done before permission was sought, at nearly twice the national rate. The approval rate is normal; what is not normal is what people are applying for.
Where the numbers come from
Planning Data
Applications submitted to Portsmouth City Council in 2025 (the latest full year), classified from each application's published description. Shares and rates use the pooled 2024-2025 window for stability.
Decision Rates
Approval rate is approvals as a share of approvals plus refusals, computed across the 1,888 decided applications in the 2024-2025 pooled window. The national benchmarks are computed the same way across all decided applications in England and Wales.
Sales Data
HM Land Registry Price Paid Data for the Portsmouth area, the latest full year's completions, with growth measured against the previous year.
The Real Applications
Open the planning applications behind the numbers.
These are real applications submitted to Portsmouth Council, from the HMO conversions that define the city to retrospective works and a clutch of refusals. Open any one to see its full record.
36 Agincourt Road PO2 7AY
A plan to convert a house to a small HMO, the application type Portsmouth files most, was turned down by the council.
See this property's full record261 Powerscourt Road PO2 7JJ
Permission was granted to convert a house into an eight person shared rental, one of the larger HMO conversions in the city's application record.
See this property's full record92 Gladys Avenue PO2 9BH
A proposal to turn a home into a nine person, nine bedroom shared house was refused, one of the roughly 1 in 8 applications the council turned down.
See this property's full record142 Copnor Road PO3 5AP
A retrospective application to split a single home into two flats, with the work already done, was granted, the built first and asked later pattern Portsmouth files at nearly twice the national rate.
See this property's full record9 Brunel Road PO2 9NP
A two storey side extension replacing a garage, plus a single storey rear extension, was approved, the most common project type submitted to the council.
See this property's full record54 Chatsworth Avenue PO6 2UQ
A single storey rear extension replacing an existing one was refused, a reminder that even routine work does not always get through.
See this property's full recordCurious about a home in Portsmouth?
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