UK landlords searching for the best storage combi boilers require space-saving solutions that deliver strong hot water flow rates for multiple bathrooms or high-demand tenancies, combining combi convenience with integrated small-cylinder storage to reduce pressure drops and improve tenant satisfaction while supporting EPC improvements.
The 5 Best Storage Combi Boilers: At a Glance
The top storage combi boilers for landlords in 2026 feature integrated hot water stores (typically 40-60 litres), high flow rates (>18 l/min), A-rated condensing efficiency for EPC C compliance, extended warranties to limit repair risks in rentals, and reliable Gas Safe servicing networks. These models suit larger flats, family homes, or HMOs without needing a full separate cylinder.
| Model | Efficiency (ErP) | Typical Unit Cost | Installed Cost (approx.) | Warranty (accredited install) | Trustpilot Rating | Key Landlord Benefit |
| Viessmann Vitodens 111-W | Up to 98% | £1,700–£2,000 | £3,500–£4,500 | Up to 12 years | 4.6/5 | Highest efficiency & hot water store |
| Vaillant ecoTEC Plus 937 | 94% | £1,600–£1,900 | £3,400–£4,400 | Up to 10 years | 4.5/5 | Quiet operation & fast recharge |
| Baxi 800 Storage Combi | 94% | £1,400–£1,700 | £3,200–£4,100 | Up to 10 years | 4.4/5 | Good value & easy servicing |
| Ideal Logic+ Store Combi | 94% | £1,300–£1,600 | £3,100–£4,000 | Up to 12 years | 4.8/5 | Strong warranty & tenant-friendly |
| Alpha E-Tec Store Combi | 93% | £1,200–£1,500 | £3,000–£3,900 | Up to 10 years | 4.7/5 | Competitive price & corrosion resistance |
Notes: Prices are 2026 UK averages for 25-35kW storage combi models with ~46L integrated stores (suitable for 2-4 bathrooms). Installed costs include standard Gas Safe fitting and flue. All are wall-mounted A-rated condensing storage combi boilers. Actual output, store size, and costs vary by property.
If you’re a landlord upgrading heating in high-demand rental properties, request a new boiler quote from Boilers 2 Go for expert sizing advice, EPC compliance support, and professional installation.
1. Viessmann Vitodens 111-W
The Viessmann Vitodens 111-W leads the best storage combi boilers for landlords with its 46-litre integrated store delivering hot water performance equivalent to a 150-litre cylinder and exceptional efficiency.
Specifications and Features
- Output: 25-35kW
- 46L stainless steel integrated store
- 18 l/min flow rate
- MatriX-Plus burner & Lambda Pro combustion control
- Hydrogen 20% blend ready
- Compact wall-mount design
Efficiency
Up to 98% seasonal efficiency with advanced condensing technology.
Estimated Cost of the Boiler Unit
£1,700–£2,000.
Costs with Installation
£3,500–£4,500.
Running Costs
High modulation and efficiency deliver £150+ annual savings versus older combis, reducing tenant bills.
Which? Trustpilot Ratings
4.6/5 Trustpilot; Which? Recommended for performance and longevity.
2. Vaillant ecoTEC Plus 937
The Vaillant ecoTEC Plus 937 excels among the best storage combi boilers for its quiet recharge cycles and reliable hot water delivery in multi-occupancy rentals.
Specifications and Features
- Output: 30-37kW
- Integrated storage cylinder
- High flow rates for simultaneous use
- IoniDetect combustion monitoring
- vSMART app compatibility
Efficiency
94% ErP A-rated.
Estimated Cost of the Boiler Unit
£1,600–£1,900.
Costs with Installation
£3,400–£4,400.
Running Costs
Efficient operation with low maintenance.
Which? Trustpilot Ratings
4.5/5 Trustpilot; frequent Which? Best Buy contender.
3. Baxi 800 Storage Combi
The Baxi 800 Storage Combi offers solid affordability in the best storage combi boilers range, ideal for landlords seeking reliable performance without premium pricing.
Specifications and Features
- Output: 25-33kW
- Integrated store for improved flow
- Stainless steel heat exchanger
- Compact footprint
Efficiency
94% ErP A-rated.
Estimated Cost of the Boiler Unit
£1,400–£1,700.
Costs with Installation
£3,200–£4,100.
Running Costs
Competitive efficiency for everyday rental use.
Which? Trustpilot Ratings
4.4/5 Trustpilot.
4. Ideal Logic+ Store Combi
The Ideal Logic+ Store Combi provides excellent value and long warranties among the best storage combi boilers, appealing to cost-conscious landlords managing multiple properties.
Specifications and Features
- Output: 25-35kW
- Built-in storage for better hot water
- Front-access servicing
- Diagnostic display
Efficiency
94% ErP A-rated.
Estimated Cost of the Boiler Unit
£1,300–£1,600.
Costs with Installation
£3,100–£4,000.
Running Costs
Good modulation reduces energy waste.
Which? Trustpilot Ratings
4.8/5 Trustpilot; praised for value.
5. Alpha E-Tec Store Combi
The Alpha E-Tec Store Combi delivers budget-friendly hot water performance in the best storage combi boilers category with strong corrosion resistance for long-term rental reliability.
Specifications and Features
- Output: 25-33kW
- Integrated store
- Stainless steel components
- Easy installation features
Efficiency
93% ErP A-rated.
Estimated Cost of the Boiler Unit
£1,200–£1,500.
Costs with Installation
£3,000–£3,900.
Running Costs
Affordable to run with solid efficiency.
Which? Trustpilot Ratings
4.7/5 Trustpilot.
How to choose the best Storage combi boilers
Choosing the best storage combi boilers for landlords rental properties means balancing integrated store size for hot water demand, efficiency for EPC ratings, warranty length to minimise repairs during tenancies, and service network coverage.
Choose the Viessmann Vitodens 111-W if you need the highest efficiency and largest effective hot water output for busy HMOs or family rentals.
Don’t choose Viessmann if your budget is tight or local engineers have limited experience with the brand.
Choose the Vaillant ecoTEC Plus 937 if quiet operation and smart controls will boost tenant satisfaction in noise-sensitive properties.
Don’t choose Vaillant if the absolute longest warranty is more important than recharge speed.
Choose the Baxi 800 Storage Combi if you want reliable performance at a competitive price for smaller rental portfolios.
Don’t choose Baxi if premium efficiency ratings are required for strict EPC compliance.
Choose the Ideal Logic+ Store Combi if extended warranties and straightforward maintenance are priorities.
Don’t choose Ideal if very high simultaneous flow rates are essential.
Choose the Alpha E-Tec Store Combi if lowest upfront costs with decent storage performance matter most.
Don’t choose Alpha if you prefer the most established premium brands.
Need a New Boiler Quote?
Upgrading to one of the best storage combi boilers helps landlords provide reliable, high-flow hot water in rentals, improve EPC scores, and reduce complaints. Request a new boiler quote from Boilers 2 Go today for tailored advice, transparent pricing, and accredited Gas Safe installation.
FAQs
Are storage combi boilers suitable for properties with very high simultaneous hot water demand?
Yes, the integrated store provides a buffer for multiple showers or taps, but extremely high-demand HMOs may still benefit from a separate system boiler and larger cylinder.
How do storage combi boilers impact EPC ratings compared to standard combis?
The higher effective hot water efficiency often improves SAP calculations and EPC scores by 1-3 bands, helping landlords meet the 2030 EPC C minimum more easily.
Are storage combi boilers hydrogen-ready for future rental compliance?
Many top models like the Viessmann Vitodens 111-W are 20% hydrogen blend ready, offering landlords a low-disruption route to lower carbon emissions.
What are the typical servicing requirements for storage combi boilers in rented properties?
Annual Gas Safe checks are mandatory; the integrated store adds minimal extra maintenance but requires checks for scale and pressure.
Can landlords deduct storage combi boiler costs as tax expenses?
Yes, replacement boilers generally qualify as revenue repairs (deductible against rental income), while efficiency upgrades may also access enhanced capital allowances or grants.
I’m Penny North, a home energy heating expert. My mission is to demystify new boilers and complex heating systems to help you achieve a warm, cosy home with lower energy bills and a smaller environmental footprint.