Commercial vs Buy-to-Let Mortgage: Which Do You Need?

The fundamental difference between a commercial mortgage and a buy-to-let mortgage comes down to property type. A commercial mortgage is used for commercial properties — offices, shops, warehouses, factories, pubs, hotels, and semi-commercial properties that combine commercial and residential elements. A buy-to-let mortgage is used for residential properties purchased as an investment to let to tenants.

This distinction matters because lenders assess these two types of property investment very differently. Commercial mortgage lenders look at the business viability of the property, tenant covenant strength, lease terms, and the borrower's experience as a commercial landlord or business owner. Buy-to-let lenders focus primarily on rental income coverage against mortgage payments, the borrower's personal income, and standard credit checks.

When applying for a commercial mortgage, lenders will want to see a clear understanding of the commercial property market, evidence of how the property will generate income, and often a personal guarantee from directors. Commercial mortgages are not regulated by the FCA, whereas buy-to-let mortgages may be regulated depending on the circumstances. Understanding these differences between commercial and residential mortgages and commercial and residential lending is essential for making an informed decision about which mortgage product suits your investment.

The range of commercial properties is far broader than most investors realise. Commercial mortgages explained: types of commercial properties available for mortgages in the UK can finance a wide variety of property types, each with distinct lending criteria and interest rate considerations:

Office property — from single suites to multi-let office buildings. Lenders assess the quality of tenants, lease terms, and the building's specification.

Retail property — high street shops, retail parks, convenience stores, and supermarkets. Lenders will look at the strength of the retail location and tenant trading performance.

Industrial and warehouse property — factories, warehouses, distribution centres, and light industrial units. This sector has seen strong demand driven by e-commerce logistics, making buying commercial property in this sector increasingly attractive.

Semi-commercial properties — buildings with both commercial and residential elements, such as a shop with a residential flat above. These require specialist semi-commercial mortgage products and careful assessment of both the commercial and residential parts.

Specialist property types — pubs, hotels, restaurants, care homes, nurseries, petrol stations, and leisure facilities. Each property type has its own niche of lenders with appetite.

The property type directly affects your lending criteria, interest rates, and maximum LTV. A mainstream office with strong tenants might attract 75% LTV at competitive commercial rates, while a pub might be limited to 60% LTV at higher rates. Mortgage brokers experienced in commercial property investment can identify the best lender and the property for your specific situation.

Interest rates for commercial mortgages tend to be higher than buy-to-let rates due to the higher risk profile that lenders associate with commercial property. Rates tend to start from around 5.50% for strong commercial propositions, rising to 9.49% or more for complex or higher-risk cases. Interest rates for commercial loan products reflect the additional complexity of commercial lending criteria.

Buy-to-let mortgage rates are generally lower, starting from around 4.50% for standard residential investment properties. The lower interest rates reflect the more liquid nature of residential properties and the typically lower risk of tenant default. For a buy-to-let property, lenders can rely on consistent residential demand and simpler valuation metrics.

Beyond interest rates, the costs involved differ. Commercial mortgages typically carry higher arrangement fees (1–2% of the loan amount), more expensive valuations (RICS commercial valuations cost more than residential valuations), and higher legal fees due to the greater complexity of commercial transactions. Mortgage interest payments may be structured differently depending on the property type.

For buy-to-let mortgages, stamp duty is a significant cost consideration. Since April 2016, buy to let property purchases attract an additional stamp duty surcharge on top of standard rates, and from April 2025 this increased to 5%. Interest rates tend to be higher for commercial properties because lenders view them as higher risk commercial real estate investments. Whether you choose a fixed rate, variable rate, or interest-only mortgage structure, the type of property you are financing directly affects the rates available. Both commercial and residential investors need to provide comprehensive financial documentation, though buy-to-let applications are typically more standardised.

Commercial buy-to-let mortgages and standard commercial mortgages have different cost profiles. Business rates are paid by commercial tenants under FRI leases, reducing landlord costs compared to residential properties. A commercial mortgage broker can help you compare the total cost of ownership — including mortgage payments, fees, and ongoing expenses — between commercial and buy-to-let property to make an informed investment decision. Use our commercial mortgage calculator to model scenarios.

Neither approach is inherently better — the right choice depends on your investment goals, capital, experience, and risk appetite. Here is how to think about each option:

Choose commercial property investment if: • You want higher rental yields (commercial properties often yield 5–10%) • You prefer longer lease terms and more stable income from tenants • You want tenants to take responsibility for property maintenance via FRI leases • You are looking to diversify away from the increasingly regulated residential market • You have the larger deposit required and are comfortable with commercial lending criteria • You are a commercial landlord seeking to build a portfolio of commercial properties

Choose buy-to-let property if: • You are starting with a smaller deposit and want higher LTV • You want the simplicity and familiarity of residential properties • You value the typically shorter void periods in residential markets • You want access to a wider range of lenders and mortgage products • You prefer the potentially faster capital appreciation of residential properties • You are looking to buy with a more standardised application process

Consider a mixed portfolio if: • You want to diversify your risk across both property types in a property portfolio • You have the capital and experience to manage different types of investment • You want the yield benefits of commercial with the appreciation potential of residential

Many experienced landlords and investors who started with buy-to-let portfolios eventually diversify to invest in commercial property for the higher yields and professional tenant relationships. The decision of buy to let or commercial comes down to your investment objectives. When you buy a commercial property, you gain access to higher yields but face higher lending costs compared to residential. Whether you choose a buy to let mortgage or commercial investment property, working with a specialist broker ensures you access the best rates and terms. Depending on the property, a bridging loan may also play a role in acquiring either type of asset quickly.

The lending criteria for these two mortgage types differ significantly. Understanding what lenders will want to see helps you prepare a stronger application.

For a commercial mortgage, lenders will look at: • Rental income — must cover the mortgage at 125–150% on a stressed basis for investment properties • Business accounts — 2–3 years of trading history for owner-occupied applications • Tenant covenant — the financial strength of existing or prospective tenants • Lease terms — length, break clauses, and rent review provisions • Property type and condition — some lenders avoid certain sectors • Investor experience — track record in commercial property or business • Personal guarantee — almost always required from directors or partners • Borrowing capacity — the amount you can borrow depends on income coverage and LTV

For a buy-to-let mortgage, lenders will look at: • Rental income — typically must cover the mortgage to cover the monthly repayments at a stressed rate (125–145%) • Personal income — many lenders require minimum personal income of £25,000 • Credit score — standard credit checks apply • Property value and type — standard residential valuation • Portfolio size — portfolio landlord rules (4+ mortgaged properties) trigger additional scrutiny • Limited company structure — increasingly popular for tax efficiency when buying a property

Lenders will want to see that the investment stacks up financially regardless of which route you take out a mortgage for, but the documentation and evidence requirements for commercial mortgages are considerably heavier. You can apply for a loan through either route, but commercial mortgages work differently to buy-to-let — you need to provide more when purchasing a property with a commercial lender. Borrowers must demonstrate their ability to repay the loan over the full mortgage term. With a fixed interest product, you can lock in predictable payments, while variable options may offer lower initial costs but carry the risk that rates tend to be higher over time if base rates rise. An interest-only mortgage option is available for both commercial and buy-to-let, allowing investors to buy property outright at the end of the term. You need to provide more detailed financials when applying for a commercial mortgage compared to a standard buy-to-let. Commercial mortgages are typically secured loans that require more extensive due diligence.

Semi-commercial properties sit at the intersection of commercial and buy-to-let lending. A typical example is a building with a retail unit on the ground floor and residential flats above — combining commercial and residential elements in a single property.

The mortgage treatment depends on the split between commercial and residential elements. If the commercial element represents more than 40–50% of the property's value or floor area, most lenders treat it as a commercial mortgage. If the residential elements dominate, some lenders may treat it as a buy-to-let with commercial considerations.

Semi-commercial properties can offer excellent value for investors because they combine the higher yields of commercial tenants with the consistent demand for residential accommodation. However, arranging property finance for mixed-use buildings can be more complex because fewer lenders offer semi-commercial mortgage products vs commercial or pure buy-to-let options.

A specialist mortgage broker — one of the experienced mortgage brokers in the commercial and residential space — with access to both commercial lenders and residential lenders can find the most competitive product for your semi-commercial investment. At Commercial Mortgages Broker, we help investors looking to buy semi-commercial properties navigate the lending criteria and secure the right commercial mortgage or buy-to-let product. Contact us to discuss your investment strategy and find out which mortgages work best for your property portfolio of properties. Whether you are looking to buy a residential flat or commercial premises, we help residential and commercial property investors access the right property finance.