InterBay (often referred to as InterBay Commercial) is a specialist lender that forms part of the OSB Group (OneSavings Bank), the same parent company behind Kent Reliance and Precise Mortgages.
Important Distinction: InterBay is a dedicated commercial and specialist buy-to-let lender. They do not offer standard residential mortgages for home buyers. Furthermore, they are an intermediary-only lender, meaning you cannot apply to them directly; you must access their products through a qualified mortgage broker.
They are widely respected in the industry for their ability to handle complex, high-value, and semi-commercial deals that mainstream banks typically reject.
If you have seen a buy-to-let mortgage rate advertised by Castle Trust Bank and wish to compare it against the rest of the market, you can use our free mortgage-sourcing tool below, or speak to a broker for a comparison of their commercial products.
Compare Rates
Showing Top Result Results
No results matching your criteria
Lender Details
Product Details
About InterBay
InterBay positions itself as a lender that looks for reasons to say "yes" to complex cases. Their lending philosophy is built entirely on manual underwriting and "real-life lending."
Instead of using a rigid computer scorecard ("computer says no"), InterBay assigns human underwriters to assess every application. This allows them to lend on complex assets - like a block of flats with a shop underneath, or a large House in Multiple Occupation (HMO) - by understanding the commercial reality of the deal rather than just ticking boxes.
Mortgage & Finance Products
InterBay’s product range is strictly for property investors, business owners, and developers in England and Wales.
-
Commercial Mortgages:
-
Owner-Occupier: Mortgages for business owners buying their own trading premises (e.g., offices, warehouses, industrial units).
-
Commercial Investment: Loans for investors buying commercial property to rent out to other businesses.
-
-
-
This is one of InterBay's key specialisms. They are experts in financing properties that are part residential and part commercial (e.g., a takeaway or shop with flats above).
-
They are often more flexible than high-street banks on the "commercial %" of the building value.
-
-
Specialist Buy-to-Let (BTL):
-
HMOs & MUFBs: They finance large HMOs (often up to unlimited bedrooms) and Multi-Unit Freehold Blocks (blocks of flats on a single title).
-
Limited Companies: They lend to SPVs (Special Purpose Vehicles) and trading limited companies.
-
Holiday Lets: Specialist finance for short-term rental properties.
-
-
-
Short-term loans for refurbishment or quick purchases. Note that their bridging products are often distributed through a select panel of specialist distributors ("InterBay Select").
-
Pros and Cons of InterBay
Here is a balanced overview of choosing InterBay for your finance.
Pros:
-
Complex Case Experts: They excel where high-street banks fail. If you have a complex ownership structure, a property with a short lease, or a "quirky" commercial asset, InterBay is often the solution.
-
Manual Underwriting: You get a commercial decision from a human expert. They can take a view on a borrower's wider portfolio and business background.
-
No Maximum Loan Size: They are comfortable with large loans (often multi-million pound transactions), whereas some specialist lenders cap out at £1m or £2m.
-
OSB Group Backing: Being part of a major FTSE 250 banking group gives them significant financial stability and funding power.
Cons:
-
Intermediary-Only: You cannot apply directly. You need to pay for a commercial mortgage broker to access their rates.
-
Cost: As a specialist commercial lender, their interest rates and arrangement fees (often 1.5% - 2%+) are higher than "vanilla" residential lenders.
-
Process: Commercial lending is more document-heavy than residential. You will likely need detailed business accounts, lease summaries, and asset and liability statements.
Customer Service and Reviews
Because InterBay deals almost exclusively with intermediaries, public reviews from end-borrowers are rarer than for high-street banks.
-
Broker Feedback: In the mortgage industry, InterBay is highly rated. They frequently win awards for "Best Commercial Lender" and are praised by brokers for their knowledgeable Business Development Managers (BDMs) who help structure deals before submission.
-
Service: Brokers often cite them as a reliable lender for "getting the deal done" once an offer is issued, although the initial due diligence process can be rigorous.
How to Apply
You cannot apply for an InterBay mortgage yourself.
-
Find a Commercial Broker: You must use an independent mortgage broker. It is highly recommended to use one who specialises in commercial or complex buy-to-let finance - get started here to begin a free, no-obligation chat with a broker who can help
-
Broker Assessment: The broker will package your case - collating your portfolio details, business accounts, and property leases.
-
Submission: The broker submits the case to InterBay. An underwriter will then review the file manually and may ask for further clarification on the "story" behind the investment before issuing an offer.
FAQs
They are "sister" brands under the same parent company, OSB Group. Kent Reliance tends to focus more on residential and standard specialist buy-to-let, while InterBay handles the more complex commercial and semi-commercial deals.
