Semi-Commercial Mortgage Calculator
Estimate mixed-use mortgage costs, source live lender products and apply online.
Mixed-use property — a shop with a flat above, offices with residential units, a pub with living accommodation — needs finance that assesses two income streams at once. Use the calculator to estimate your costs, then source the lenders who specialise in it.
Products are uploaded directly by lenders, so you're sourcing live, current semi-commercial deals. Once you've run your figures, shortlist what fits and apply online. Your application is then handled by Dynamic Commercial Finance, our specialist brokerage team, who fact-find your case and submit it to the lender.
What is a semi-commercial mortgage?
A semi-commercial (or mixed-use) mortgage funds property that combines commercial and residential elements under one title — most commonly a retail unit or office with flats above. Lenders assess both a commercial lease (with a business covenant) and a residential tenancy (with consumer protections), which makes these deals more complex, and more specialist, than standard buy-to-let.
The split matters
Lenders usually measure the residential-versus-commercial proportion by floor area. A property that's largely residential can qualify with specialist BTL lenders at rates closer to their BTL range; one that's largely commercial is assessed on commercial criteria, with higher rates and more conservative LTVs.
More residential
Often accesses specialist BTL pricing and criteria.
More commercial
Assessed on commercial criteria — higher rates, lower LTVs.
How the calculator works
Enter the property value, deposit, expected income, interest rate and term, and the calculator estimates your monthly payments and borrowing. Because semi-commercial blends two income types, the live products you source will reflect how each lender weighs the split.
The result is a guide, not a formal quote. Semi-commercial is individually underwritten — the products you source reflect real lender appetite.
Mixed-use filters — real lender criteria
Every filter maps to how specialist lenders assess semi-commercial and mixed-use security.
Explore related tools: buy-to-let calculator, commercial calculator, bridging calculator.
From calculation to completed application — one platform
Estimate
Model your costs with the calculator above.
Source
Browse semi-commercial products uploaded directly by lenders.
Shortlist
Save the deals that fit, with no obligation to proceed.
Apply online
Submit through the platform when ready.
We handle the rest
Dynamic Commercial Finance fact-finds and submits your case to the lender.
Semi-commercial rates and criteria in 2026
With the base rate at 3.75%, semi-commercial mortgage rates for investment purchases in 2026 sit broadly in the 5.5% to 8% range:
- Lower end (≈5.5%–6.5%) — a dominant residential element, strong tenant covenants on both parts, established income, a solid track record and LTV below 65%.
- Upper end (≈7%–8%) — a larger commercial element, short remaining lease terms on the commercial part, first-time commercial investors, or higher LTVs.
LTVs typically reach around 70–75%, and lenders assess affordability on the combined income, often with a debt-service coverage requirement. Deposits of 25–30%+ are usual.
Indicative rate ranges only — August 2026. Live lender-uploaded products are the source of truth.
Why use DyneSourcer for semi-commercial?
Products uploaded by lenders
Live mixed-use deals, not stale listings.
Calculate, source, shortlist and apply in one place
The full journey for semi-commercial finance — not just a cost estimate.
Specialist brokerage support
Dynamic Commercial Finance presents the residential/commercial split and tenant covenants properly, which is where these cases are won or lost.
Whole-of-market view
Specialist BTL and commercial lenders together.
Semi-commercial FAQs
Common questions about mixed-use mortgages, deposits, rates and regulation on DyneSourcer.
What counts as a semi-commercial property?
Property combining commercial and residential use under one title — for example a shop, office or pub with flats above. Lenders usually assess the split by floor area.
What happens after I apply?
Your application goes to Dynamic Commercial Finance, our specialist brokerage team, who fact-find your case and submit it to the lender.
How much deposit do I need?
Typically 25–30%+, with LTVs usually up to around 70–75%. A larger deposit and a stronger residential weighting help secure better pricing.
Is a semi-commercial mortgage regulated?
Most investment semi-commercial lending is unregulated business lending. Owner-occupier cases can differ — confirm which applies to you.
How does the commercial/residential split affect my rate?
A more residential property often accesses specialist BTL pricing; a more commercial one is assessed on commercial criteria, usually meaning higher rates and lower LTVs.
Calculate, source and apply — all in one place.
Model your mixed-use mortgage costs, source live products from UK lenders, shortlist and apply online. Dynamic Commercial Finance handles the rest.
Your property may be repossessed if you do not keep up repayments on your mortgage. Most investment semi-commercial mortgages are not regulated by the Financial Conduct Authority.
Dynesourcer Ltd is an IAR of Dynamic Commercial Finance Ltd. Products updated August 2026.