Bridging Finance for Commercial Property: How It Works

Bridging finance for commercial property is short-term, interest-first lending used to buy or refinance a commercial building that a term mortgage will not yet fund. The reason a term lender holds back is almost always the same: the building does not yet produce income. It is empty, part-let, mid-refurbishment, or being repositioned for a new tenant, and a commercial mortgage wants to see rent on the ground before it commits. A bridge fills that gap. It funds the purchase (and often some light works), holds the asset while it is let, and is then repaid from a sale or a refinance onto a commercial term mortgage once the building is income-producing.

The single feature that sets a commercial bridge apart from the other reasons investors bridge is the valuation basis. An empty commercial unit is not lent against on what it would be worth let and yielding. It is lent against on a vacant-possession basis, a discount to the investment value, and that discount is where most of the surprises in commercial bridging live. Get the valuation basis right and the rest of the deal follows. This guide works through what a commercial bridge is, the vacant-possession versus investment valuation that drives it, why the tenant's covenant decides the exit, what it costs, and the tax that sits alongside the interest.

A note on scope and what this guide is. This is an educational guide to how commercial bridging works. It is not a financial promotion, it does not arrange, compare or recommend finance, and it does not invite you to apply for a loan. Bridging for a genuine business or investment purpose sits outside the consumer-credit and regulated-mortgage perimeters (the business-purpose and £25,000-plus exemptions in the Regulated Activities Order 2001), but promoting the credit itself is restricted under section 21 of the Financial Services and Markets Act 2000. So we explain the mechanics and the tax, and we point you to an FCA-authorised broker or lender when it is time to price a deal. If any part of the security would be your own home, that is a regulated product and outside the scope of this guide; speak to an FCA-authorised mortgage adviser.

Why a term mortgage does not fit an empty commercial building

A commercial term mortgage is underwritten on income. For an investment purchase, the lender tests the rent against an interest cover ratio; for an owner-occupier, it tests the trading affordability of the business that will occupy the premises. An empty building offers neither. There is no rent to cover the interest and, if it is being bought as an investment rather than to trade from, no occupying business to carry the loan. The term lender's answer is usually to decline until the unit is let, or to offer so little that the deal does not work.

That is the void a bridge is built for. A bridging lender underwrites the security and the exit rather than current income. It asks what the building is worth today, empty, and how the loan will be repaid. If the answer is a credible plan to let the unit and refinance onto a term mortgage, or to sell, the bridge can proceed on a timetable a term lender cannot match. The trade-off is cost and time: bridging is priced by the month and meant to be short. It is a tool to make a building mortgageable, not a place to leave debt.

The valuation basis: vacant possession versus investment value

This is the distinguishing point of commercial bridging, and it is worth slowing down on. A commercial building can be valued two ways, and the gap between them decides how much you can borrow.

• Vacant-possession value is what the building would sell for with no tenant in place. A buyer of an empty unit carries the void period, the cost of finding a tenant, and the risk that letting takes longer or achieves less rent than hoped, so the vacant-possession figure is discounted to reflect all of that.
• Investment value is what the building is worth let and income-producing, arrived at by capitalising the rent at a yield. A unit let on a long lease to a solid tenant is a bond-like income stream, and it is usually worth more, sometimes materially more, than the same building standing empty.

A surveyor working to the RICS valuation standards will often report both figures for a commercial asset. While the building is empty, the bridging lender lends against the vacant-possession number, because that is what it could recover if it had to sell the security tomorrow. This is why owners are so often caught out: they see the building's potential let value, but the bridge is sized against the lower empty value. The whole purpose of the deal is to close the gap by letting the unit, which converts the vacant-possession value into the higher investment value that the exit mortgage will work from.

Tenant covenant and lease length drive the exit

Because the bridge repays from an investment-basis refinance, the thing that unlocks it is a tenant. Not just any tenant: the covenant (the financial strength of the business taking the lease) and the terms of the lease decide how much the exit is worth. Underwriters look at the tenant's trading history and accounts, the length of the lease, any break clauses, the repairing obligations, and whether the rent is sustainable for that use in that location.

A fifteen-year lease with no early break to an established national operator supports a high investment value and a keen commercial mortgage. A three-year lease to a brand-new business with a personal guarantee supports far less, because the income is thinner and the re-letting risk is higher. When you plan a commercial bridge, the letting strategy is not an afterthought to be sorted once you own the building; it is the exit, and the exit is what the bridging lender is really underwriting. A realistic view of who will take the space, at what rent, on what lease, is worth more to your application than shaving the monthly rate.

What a commercial bridge costs

Commercial bridging is quoted as a monthly rate, not an annual one, which trips up borrowers used to mortgage pricing. As a guide, first-charge commercial bridging rates sit in a band of roughly 0.7% to 1.1% per month, as at July 2026, with the exact figure driven by the loan-to-value, the property type, the condition of the building, the strength of the exit and the borrower's experience. Rates move with the Bank of England base rate and with lender appetite, so treat any figure here as an illustration and verify current pricing with a broker or lender before you rely on it.

On loan-to-value, a vacant commercial unit typically borrows around 65% to 70% of its vacant-possession value on a first charge, as at July 2026, with prime, easily re-let space toward the top of that band and specialist or single-use buildings lower. Remember that this is a percentage of the lower, empty value, so the cash advanced is smaller than a percentage of the let value would suggest. On top of the interest, budget for the wider cost stack: an arrangement fee (commonly around 1% to 2% of the loan), a commercial valuation (more than a residential one, and sometimes needing an environmental report on industrial sites), legal fees for both sides, and often an exit fee. Interest is usually rolled or retained rather than paid monthly, which means it is deducted from the loan at the outset and compounds, so the amount you draw in hand is less than the headline facility.

The exit: a commercial term mortgage once it is let

The normal exit from a commercial bridge is a refinance onto a commercial term mortgage once the building is let and income-producing, or a sale of the asset. The refinance is where the valuation shift pays off. A signed lease to a decent tenant does two things at once: it gives the term lender the rent it needs to underwrite an interest cover ratio, and it moves the valuation from the vacant-possession basis onto the investment basis, usually a higher figure. The building that borrowed 65% to 70% of its empty value on the bridge can, once let, support a term mortgage sized against its higher let value.

If the plan is to refurbish before letting, the works and the letting run in sequence: the bridge funds the purchase and the light works, the unit is brought to a lettable standard, a tenant is signed, and the term mortgage takes over. Where the works are more than cosmetic, a refurbishment bridge with staged drawdowns can be the better structure, and our guide to bridging finance for refurbishment covers that route. For the term facility that repays the bridge, our commercial mortgages guide explains how the exit lender underwrites the rent, the covenant and the loan-to-value.

A worked example: a £500,000 vacant unit

Consider an investor buying a vacant high-street retail unit with offices above for £500,000. The building is sound but empty, the previous tenant having left, and no commercial mortgage lender will fund an untenanted property. A surveyor reports two figures: a vacant-possession value of around £500,000 (in line with the price), and an estimated investment value nearer £620,000 once let on a standard commercial lease, reflecting the rent capitalised at a market yield.

The bridging lender lends against the vacant-possession value. At 68% of £500,000 the first-charge facility is about £340,000, so the investor funds the roughly £160,000 balance plus fees from their own resources. Over a nine-month term at an illustrative 0.85% per month with interest retained, the interest is in the region of £26,000, and with an arrangement fee of around 1.5% (£5,100), a commercial valuation and legals on both sides, the true cost of the bridge is well above the headline monthly rate. During the term the investor markets the unit and signs a ten-year lease to an established local operator. That lease lifts the valuation onto the investment basis (about £620,000) and gives a term lender the rent to work with. The investor refinances onto a commercial term mortgage at, say, 70% of the £620,000 let value (about £434,000), which clears the bridge and its rolled interest and releases the property into a long-term hold. The bridge did one job: it turned an unmortgageable empty building into a let, income-producing, mortgageable asset.

The risks, and the fence around your own home

The core risk of a commercial bridge is the exit. If the letting takes longer than planned, or the tenant you lined up falls away, the interest keeps accruing and the term can run out before the refinance is in place. That exposes you to default interest at a much higher rate, pressure to sell into a weak market, and enforcement against the security and any personal guarantees the directors gave. A sensible term with headroom, a realistic letting timetable, and genuine evidence of tenant demand are worth more than a marginally lower rate. Void periods on commercial property can be long, and a bridge is an expensive place to sit through one.

On the regulated boundary, a purely commercial bridge for a business or investment purpose is unregulated, which is why this guide can explain it. The line to watch is dwelling use. Under FCA PERG 4, a loan can become a regulated mortgage contract where 40% or more of the property is used as a dwelling by the borrower or a close relative. A shop with a flat above that you will let to third parties is normally fine as a commercial deal, but if any part of the security is your own home, the position changes and you should speak to an FCA-authorised mortgage adviser rather than treat it as a commercial bridge. The trade body for the sector, the Bridging and Development Lenders Association, sets standards its members work to and is a useful reference point when you assess a lender.

The tax angle: interest and the building

Two tax points matter on a commercial bridge, and both are more favourable than the residential equivalent. First, the interest. On commercial property the interest is generally deductible in full against rental or trading profit, because the Section 24 finance-cost restriction that caps residential landlords at a basic-rate 20% reducer applies to dwellings only. A commercial investor deducts the interest at their marginal rate; a company deducts it under the loan-relationship rules. How rolled or retained interest and the arrangement and valuation fees are relieved (and when) depends on your structure, and our guide to whether bridging loan interest is tax deductible works through the individual, company and commercial positions in detail. For the wider picture on how commercial letting is taxed, see our commercial property tax guide for landlords.

Second, the building itself. A commercial purchase is exactly the moment to review capital allowances on the commercial property. Fixtures embedded in the building, heating, air conditioning, wiring, sanitaryware and certain fitted equipment, can qualify for plant and machinery allowances that relieve future profit, and the availability turns on the history of prior claims and a fixtures election settled at purchase. A bridge does not change the allowances, but the transaction it funds is when the fixtures position should be established, before the paperwork is done and the chance is lost.

Where a commercial bridge sits in the toolkit

A commercial bridge is a means to an end. It exists to carry an empty or unmortgageable commercial building across the gap between purchase and income, so that a commercial term mortgage can take over once the unit is let. If you are researching the short-term product itself, our bridging loans guide explains charges, open versus closed bridging, rolled versus serviced interest and exit strategy in full, and the bridging loan calculator lets you estimate the monthly cost and the rolled-up interest over a term. When the building is let and you are ready for the long-term facility, the commercial mortgages guide covers the exit. Throughout, remember the point that separates commercial bridging from every other kind: the loan is sized against the empty value, and the whole job is to convert that into the higher let value the mortgage will work from.