How Are Commercial Mortgage Rates Determined in the UK?

Ask for a commercial mortgage quote and you won't get a single number pulled from a published rate sheet. You'll get a question, or several. That's not a lender being difficult. It's because commercial mortgage pricing isn't a fixed menu, it's built individually for every deal, from a mix of ingredients that shift depending on what you're buying and who you are.

Understanding those ingredients won't get you a better rate on its own, but it explains why two seemingly similar borrowers can be quoted very different numbers.

Bank of England held base rate at 4.25% in June 2026 - waiting for inflation to cool.

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The starting point: what's the money actually costing the lender?

Every commercial mortgage rate begins with the lender's own cost of funding, and this is where two terms come up constantly: the base rate and SWAP rates.

- The Bank of England base rate underpins variable and tracker-style commercial mortgages. If your rate is priced as "base rate plus a margin," this is the number it's tracking.

- SWAP rates are what most fixed-rate commercial mortgages are priced against instead. A SWAP rate reflects what the financial markets expect interest rates to average over a given period, say five years, and it's often a better predictor of fixed-rate pricing than the base rate is, since fixed deals need to account for where rates are heading, not just where they are today.

When SWAP rates move, fixed commercial mortgage pricing tends to follow within days. When the base rate moves, it's the variable and tracker deals that respond most directly.

On top of that: the lender's margin

Once the underlying cost of funds is set, the lender adds a margin on top. This is where the rest of your application starts to matter, because the margin is where risk gets priced in.

What pushes your margin up or down?

A long list of factors, but the ones that matter most consistently are:

- Loan-to-value (LTV). A lower LTV, meaning a bigger deposit, generally earns a lower rate. Less risk for the lender, better pricing for you.

- Property type. Standard commercial property (offices, shops, industrial units) tends to price more competitively than specialist assets like care homes, hotels, or petrol stations.

- DSCR (Debt Service Coverage Ratio). A deal with strong income cover relative to the debt looks safer, and safer usually means cheaper.

- Trading history and accounts. Established businesses with several years of solid accounts typically access better pricing than start-ups.

- Tenant strength, for investment property. A long lease with a strong covenant reduces risk considerably.

- Owner-occupier vs investment. These are sometimes priced differently depending on the lender's appetite.

- Credit history. Adverse credit doesn't necessarily rule out an application, but it usually affects the price.

Fixed vs variable: does one cost more?

Not automatically, it depends on market conditions at the time. Fixed rates offer certainty, your payment doesn't move for the term you've locked in, which some lenders and borrowers price as worth paying for. Variable and tracker rates move with the base rate, which can work in your favour if rates fall, and against you if they rise.

Neither is inherently the "cheap" option. It depends on where SWAP rates and the base rate sit relative to each other at the point you're borrowing.

Why can't lenders just publish a rate table?

Because unlike a residential mortgage, where the property (a standard house) is broadly comparable from one application to the next, commercial property varies enormously. A rate that makes sense for a low-LTV office purchase backed by a 15-year lease bears little relation to a rate for a higher-LTV purchase of an empty industrial unit with no tenant in place.

Each deal is priced on its own merits, which is precisely why "what's the rate" is rarely a question with a one-line answer.

What can you actually do to influence your rate?

Quite a lot, as it happens:

• Increase your deposit to lower the LTV

- Strengthen your DSCR by considering a longer term or a bigger deposit

• Present clean, well-organised accounts and a clear business case

• Choose a property type the lender is comfortable with

- Approach lenders whose appetite genuinely matches your deal, rather than applying broadly and hoping

The mistake people often make

Borrowers sometimes fixate on chasing the lowest headline rate they've seen mentioned online, without realising that number was priced against a completely different deal, a lower LTV, a stronger tenant, a different property type entirely. The rate that matters is the one your specific application will actually be offered, not the one that appears in someone else's case study.

The bottom line

Commercial mortgage rates start with the underlying cost of money, tracked through the base rate for variable deals and SWAP rates for fixed ones, and then have a margin added on top that reflects the risk of your specific deal. LTV, property type, DSCR, and trading history all move that margin up or down.

There's no fixed rate card because there's no fixed deal. Every application is priced on its own terms, which is exactly why getting the fundamentals right, deposit, income cover, and paperwork, matters more than shopping for a number you saw somewhere else.

Disclosure: Money Pilot Ltd (FRN: 968705) is an Appointed Representative of Yellow Stone Finance Group Ltd which is authorised and regulated by the Financial Conduct Authority (FRN: 814533). Yellow Stone Finance Group Ltd is a credit broker not a lender. Money Pilot Ltd is Registered in England and Wales No: 13621432. You should always make sure you are able to afford any repayments as late or missed payments can affect your credit rating and access to future finance.

YOUR PROPERTY MAY BE REPOSSESSED IF YOU DO NOT KEEP UP REPAYMENTS ON A MORTGAGE OR ANY OTHER DEBT SECURED ON IT.