September 2025 data shows transaction prices holding modest annual growth of 1-2%, mortgage approvals stable at 65,000 per month, and regional performance patterns continuing as established over recent months. Asking prices posted a weak 0.4% monthly recovery after summer declines, turning negative year-on-year for the first time since January 2024.
The data confirms the market structure that has been visible since summer: northern and affordable markets delivering 3-10% annual growth, southern and expensive markets achieving 0-1% or negative growth, and transaction volumes steady at pre-pandemic levels despite higher interest rates.
1) Rightmove: Asking prices stabilise after summer correction
Rightmove's methodology: Tracks asking prices from new listings, providing the earliest indicator of seller pricing behaviour and market sentiment shifts.
September 2025 key points:
- Average asking price: £370,257 (up 0.4% month-on-month)
- First monthly increase since May
- Annual change: -0.1% (first negative reading since January 2024)
- Sales agreed: +4% year-on-year
What this index tells us about the UK housing market:
Summer correction complete: September's +0.4% uptick follows three consecutive monthly declines (June -1.2%, July -1.2%, August -1.3%) that removed £10,777 from peak asking prices. However, this recovery is weaker than typical September seasonality, which averages +0.6% at this time of year.
Annual pricing now negative: The -0.1% year-on-year decline represents the first negative annual comparison since January 2024, driven entirely by London and southern England underperformance. London asking prices fell -1.5% monthly and are down -1.1% annually, while the North East—the least expensive region—gained +1.2% monthly and holds +0.5% annual growth.
Activity remains robust despite pricing adjustments: Sales agreed running 4% ahead of September 2024 demonstrates that competitive pricing continues to drive transactions. Rightmove reports that homes for sale are 10% higher than last year in southern England versus just 2% elsewhere, with properties taking five days longer to find buyers in the south.
Supply-demand imbalance pressuring southern pricing: The 10% inventory increase in southern England—five times higher than elsewhere—creates material downward pressure on asking prices in these markets. Sellers face significantly more competition for a relatively static buyer pool, forcing aggressive pricing to secure transactions. This structural oversupply in expensive southern markets contrasts sharply with more balanced supply conditions in affordable northern regions, explaining much of the regional performance divergence beyond pure affordability factors.
Budget uncertainty acknowledged but not yet impacting: Rightmove notes that speculation around property tax changes "began swirling in mid-August" with the Budget not arriving until 26th November. While their real-time data shows no immediate reaction from movers, they acknowledge that "jitters around what could happen risk slowing the parts of the market that are already underperforming"—specifically London and southern England where 59% of sales exceed £500,000 versus 22% elsewhere.
The asking price data confirms that sellers have accepted the new pricing reality established over summer, with competitive pricing remaining essential to achieving sales in the high-supply environment.
2) Halifax: Transaction prices edge down but remain broadly stable
Halifax methodology: Based on mortgage approval data from major lender transactions, reflecting actual agreed prices rather than initial seller aspirations.
September 2025 key points:
- Average property price: £298,184 (down 0.3% month-on-month)
- Annual growth: +1.3% (slowest rate since April 2024)
- Year-to-date: +0.3% (essentially flat)
- Regional leadership: Northern Ireland at +6.5% annually
What this index tells us about the UK housing market:
Monthly volatility within annual stability: Halifax Head of Mortgages Amanda Bryden characterises September's -0.3% decline as reflecting "a housing market that has remained broadly stable, prices are up +0.3% since the start of the year." The deceleration from August's +2.0% annual growth to September's +1.3% represents the slowest annual rate in five months, but Halifax continues to "expect modest growth through the remainder of the year."
Regional divergence remains the dominant pattern: Northern Ireland's +6.5% annual growth (down slightly from +7.9% last month) leads all regions, followed by Scotland (+4.5%) and the North East (+4.8%). Meanwhile, the South West recorded a second consecutive annual decline at -0.2%, while London (+0.6%) and South East (+0.2%) show minimal growth.
First-time buyer segment outperforming: The typical first-time buyer home costs £236,811, up +1.7% year-on-year—stronger than the overall market. This suggests that affordable entry-level properties continue finding buyers despite broader market softness, reinforcing the pattern where lower-priced segments demonstrate greater resilience.
Affordability improvements supporting demand: Halifax notes that "a relatively lower mortgage rate environment and steady wage growth have helped support buyer confidence" while acknowledging that "affordability remains a challenge" at higher price points.
Halifax's interpretation of their own data suggests September's monthly decline represents noise within stability rather than the start of sustained weakness, with their forward guidance unchanged.
3) Nationwide: Steady growth continues with regional deceleration evident
Nationwide methodology: Uses building society's mortgage approval data to track transaction prices, with additional focus on affordability metrics and economic context.
September 2025 key points:
- Average price: £271,995 (up 0.5% month-on-month)
- Annual growth: +2.2% (marginally up from August's +2.1%)
- Q3 quarterly growth: +0.4%
- Mortgage approvals: Stable around 65,000 per month
What this index tells us about the UK housing market:
Activity and growth in equilibrium: Chief Economist Robert Gardner notes that "the annual pace of UK house price growth was little changed in September at 2.2%" while "the number of mortgages approved for house purchase have been hovering at around 65,000 cases per month, close to the pre-pandemic average (despite the higher interest rate environment)."
Underlying conditions remain supportive: Gardner emphasises that "unemployment is low, earnings are rising at a healthy pace, household balance sheets are strong and borrowing costs are likely to moderate a little further" as Bank Rate is expected to be lowered in coming quarters. This suggests that fundamental demand drivers remain intact even as monthly price movements show volatility.
Regional Q3 data reveals southern softening: Nationwide's quarterly regional indices for Q3 (July-September) show that most regions experienced modest slowdowns in annual house price growth. Critically, the Outer South East—traditionally a strong performer—saw annual growth decelerate from +2.6% in Q2 to just +0.3% in Q3, making it the weakest performing region in England.
Northern England maintaining momentum: Average prices in Northern England (North, North West, Yorkshire & Humber, East Midlands, West Midlands) were up +3.4% year-on-year, with the North achieving +5.1% growth. Meanwhile Southern England (South West, Outer South East, Outer Metropolitan, London, East Anglia) slowed to just +0.7% annual growth.
Property type divergence widening: Semi-detached properties led price growth at +3.4% annually, while flats declined -0.3% year-on-year. Over the past decade, flats have increased only 20% versus terraced houses rising over 40%—a structural divergence reflecting changing buyer preferences and post-pandemic work patterns.
Nationwide's data confirms that while national averages show stability, the composition beneath reveals accelerating regional divergence and property type stratification.
4) ONS: July data shows continued regional leadership by affordable markets
ONS methodology: Uses data from HM Land Registry, Registers of Scotland, and Land & Property Services Northern Ireland to track final transaction prices across all residential property sales, including cash purchases.
July 2025 (most recent data) key points:
- Average property price: Data pending full release
- Most comprehensive coverage: Includes all cash and mortgage transactions
- Regional patterns: Historically confirms mortgage lender index trends
What this index tells us about the UK housing market:
ONS data, while lagging by approximately two months, provides the most comprehensive view of actual transaction prices by including cash purchases alongside mortgaged transactions. Historical patterns show ONS data typically confirms the regional performance hierarchy seen in Halifax and Nationwide indices, with affordable northern markets consistently outperforming expensive southern regions.
The ONS index remains the authoritative source for understanding complete market coverage, particularly for investors and developers focused on cash-buyer segments or areas with higher proportions of outright purchases.
Regional performance and strategic implications
September 2025 confirms the regional framework established throughout the year. Strong performers (Northern Ireland +6.5-9.6%, North England +3.4-5.1%, North West +3.2-3.9%) continue delivering growth well above national averages, while southern markets struggle (London +0.6%, South East +0.2-0.3%, South West -0.2%).
The critical development is the Outer South East's sharp deceleration—from +2.6% in Q2 to +0.3% in Q3. This 2.3 percentage point drop in three months reflects structural affordability constraints in higher-priced commuter markets, not seasonal variation.
Transaction velocity reinforces the regional divide: properties in southern England take five days longer to find buyers than northern markets, with direct implications for development finance cash flow planning.
Investment implications for development finance
September 2025 confirms the market equilibrium we identified in August: transaction prices holding modest growth while activity stabilises at sustainable levels. For development finance, this rewards disciplined regional selection over market timing strategies.
Regional strategy remains essential: The 9+ percentage point gap between best and worst performing regions continues the pattern established throughout summer 2025. Development strategies should focus on markets achieving 3%+ annual growth where demand fundamentals support both pricing power and faster transaction velocity.
Exit pricing discipline: Use transaction data (Halifax/Nationwide showing 1-2% growth) rather than asking prices (Rightmove at -0.1%) for exit valuations. The divergence between asking and transaction prices—a theme since June's data—demonstrates that completions occur within realistic pricing bands, not at aspirational listing levels.
Budget uncertainty creates segmented risk: Property tax speculation affects £500k+ properties in London and southern England, where 59% of transactions fall into this bracket versus 22% nationally. Projects outside this segment face minimal Budget-related risk, with September activity data showing stable mortgage approvals across all other price points and geographies.
Key factors to monitor through autumn
Budget outcome (26th November): Markets most exposed to speculated stamp duty changes and mansion taxes (London, southern England, £500k+ segment) should see either relief rally if changes are benign, or price adjustment if punitive measures are confirmed.
Southern market trajectory: The Outer South East's sharp Q3 slowdown (from +2.6% to +0.3%) warrants monitoring. Continued deceleration would confirm structural affordability constraints in high-value commuter markets, while stabilisation would suggest temporary adjustment rather than sustained weakness.
Summary
September 2025 shows the housing market operating in equilibrium: transaction prices growing 1-2% annually, mortgage approvals stable at 65,000 monthly, and clear regional differentiation favouring affordable markets.
For development finance, the strategic framework is straightforward: focus on markets delivering 3%+ growth with faster transaction times, use transaction data rather than asking prices for exit assumptions, and assess Budget risk only for £500k+ southern exposure. The fundamentals—stable approvals at pre-pandemic levels, improving affordability, and wage growth—support this operating environment continuing through year-end.
FAQs
Based on our analysis of September 2025 market data, here are the key questions property investors and developers are asking about current conditions.
Should I be concerned about Halifax's negative monthly figure in September?
No. Halifax themselves characterise the -0.3% decline as reflecting "a housing market that has remained broadly stable" with prices up just +0.3% year-to-date. Monthly volatility is normal, particularly when transaction volumes are relatively modest.
The key is that Halifax maintains their guidance for "modest growth through the remainder of the year" and emphasises that underlying conditions remain supportive. When viewed quarterly rather than monthly, the picture shows stability rather than concerning weakness.
How significant is the Budget uncertainty for development projects?
It depends entirely on your price point and geography. If you're developing properties exceeding £500k in London or southern England, Budget uncertainty creates genuine risk—59% of London transactions fall into this bracket where speculated tax changes would apply, versus just 22% nationally.
However, for affordable residential projects below £500k outside the south, the impact appears minimal. September activity data shows no material change in transaction volumes for these segments, with mortgage approvals remaining stable at 65,000 monthly across all price points.
Which regions offer the best risk-adjusted opportunities for SME developers right now?
Focus on markets delivering 3%+ annual growth with proven transaction velocity. Northern Ireland (6.5-9.6% growth), the North (5.1%), North West (3.2-3.9%), and Yorkshire (3.8%) combine lower land costs, faster sales times, and genuine price growth.
The Outer South East's deceleration from +2.6% to +0.3% in one quarter demonstrates that even traditionally strong southern markets face affordability headwinds. The 9+ percentage point gap between best and worst performing regions isn't temporary—it's the established market structure reflecting fundamental affordability dynamics.
How should I adjust my development appraisals for current market conditions?
Use transaction prices (Halifax/Nationwide showing 1-2% growth) rather than asking prices (Rightmove at -0.1%) for exit assumptions. Build in regional velocity differences—properties in southern England take five days longer to find buyers than northern markets, which has material cash flow implications.
Factor in stable rather than growing mortgage approval volumes (65,000 monthly has been consistent for months), and avoid assuming seasonal surges that may not materialise. The market rewards conservative assumptions and disciplined regional selection over optimistic timing bets.
What should I watch for in October's data to validate or challenge this stable market view?
Three key indicators: First, whether mortgage approvals remain around 65,000 or show material deviation. Second, whether the Outer South East's sharp Q3 deceleration continues or stabilises. Third, the immediate market reaction to Budget announcements on 26th November—particularly in the £500k+ southern segment where policy risk is concentrated. If approvals hold steady, southern markets stabilise, and Budget changes prove less punitive than feared, the stable equilibrium thesis strengthens. Any significant moves outside these parameters would warrant reassessing the market structure.
Analysis compiled October 2025 using official housing market data from Rightmove, Halifax, Nationwide, and ONS, combined with transaction and lending statistics from Bank of England and HMRC sources.
