Bridging Loan Delay Calculator

The planned term on a bridging loan is rarely the actual term. Sales take longer than expected, refinance applications encounter queries, works overrun, and the exit that was due at month 9 lands at month 11. Each additional month costs money, and in many cases the cost per month during an extension is higher than during the original term because the rate may increase and extension fees apply on top. Knowing what a delay costs before agreeing the original facility is how well-structured deals avoid becoming financially strained ones.

This tool models the full cost of a bridging extension: the additional interest at a potentially higher rate, the extension fees charged per month, and the daily cost of the facility during both the planned term and the extension period. All figures are illustrative and the tool does not constitute financial advice.

At a Glance

  • The extension rate is often higher than the planned term rate, and extension fees apply on top.

    Many lenders charge a higher monthly rate during the extension period, typically 0.25% to 0.50% above the original rate. On top of that, an extension fee of around 1% of the gross loan per extension month is common. The combined effect means that each extra month during an extension costs meaningfully more than each month during the planned term. The tool models both the rate increase and the extension fee separately so the borrower can see where the additional cost comes from.

    Extension rate and fee mechanics

  • The daily cost figure is the most practical metric for project planning and completion meetings.

    A bridging loan priced monthly is difficult to translate into the daily reality of a delayed project. The daily cost panel converts the monthly figures into a per-day and per-week cost during both the planned term and the extension, making the financial pressure of a two-week overrun tangible in a way that monthly figures alone do not.

    The daily cost of delay

  • Choosing the right original term is the most effective way to avoid extension costs entirely.

    A term that covers the realistic exit timeline plus one to two months of buffer typically costs less in additional retained interest or rolled-up compounding than an extension would cost in higher rates and fees. The tool quantifies both sides: the planned cost column shows what the buffer months add, and the extension column shows what happens without them.

    Building a buffer into the original term

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How they work, what they cost, and what to consider before applying

Interactive tool

Bridging loan delay calculator

Model the cost of a bridging loan extension, including additional interest, extension fees, and the daily cost of each extra day on the facility.

All figures are illustrative. Nothing you enter is stored or transmitted.

£300,000
0.75%
9 months
1.5%
Retained Rolled-up Serviced
0%

Extension scenario

3 months
1%

Some lenders charge a higher rate during extensions

1%

Charged on the gross loan for each extension month

What every extra day costs

Retained interest is simple monthly interest on the gross loan. Rolled-up interest compounds monthly. Serviced interest is paid monthly. Extension interest is calculated at the extension rate on the balance at the end of the planned term. Extension fees are calculated on the gross loan per extension month. Daily cost figures use 30.44 days per month as an average. This tool does not constitute financial advice. All figures are illustrative only.

About this tool

What it models

Planned term cost vs extension cost with rate uplift and fees

Enter the gross loan, rate, term, and fees for the planned facility. Then set the extension scenario: how many additional months, whether the rate increases, and what extension fee applies per month. The tool calculates the full cost under both scenarios and shows the difference across interest, fees, and total cost in four comparison tiles.

Key features

Daily cost, extension fee modelling, and interest structure selector

The daily cost panel translates monthly figures into per-day and per-week costs during both the planned term and the extension period. The extension fee slider models the per-month penalty that most lenders charge for extending beyond the agreed term. The interest structure selector (retained, rolled-up, serviced) ensures the calculations reflect the actual loan mechanics.

How to use the delay calculator

The tool is most useful when the borrower has a specific facility in mind and wants to stress-test the exit timeline. The default values show a common scenario where a 9-month bridge extends by 3 months at a higher rate with extension fees, which is a realistic modelling exercise for any refurbishment or sale-exit deal.

1

Enter the planned facility details

Set the gross loan, monthly rate, planned term, arrangement fee, exit fee, and interest structure to match the quote or illustration being modelled. The interest structure matters because rolled-up interest during the planned term compounds, making the starting balance for the extension period higher than on a serviced or retained structure.

2

Set the extension scenario

Choose the number of extension months, the extension rate (which may be the same as the planned rate or higher, depending on the lender), and the extension fee per month. If the lender’s extension terms are not yet known, typical assumptions are: rate 0.25% to 0.50% above the original, and an extension fee of 1% of the gross loan per month. These figures are common across the UK bridging market and provide a realistic stress-test.

3

Read the comparison and the daily cost panel

The two result cards show the full cost under each scenario. The four difference tiles isolate the additional interest, extension fees, total additional cost, and extra redemption. The daily cost panel converts these into per-day and per-week figures for both the planned term and the extension, making it possible to answer “what does a two-week overrun actually cost?” with a specific figure.

Extension rate and fee mechanics

When a bridging loan runs beyond the agreed term, the lender is exposed to the facility for longer than planned. Most lenders manage this by offering a formal extension, typically month by month, at terms that are less favourable than the original facility. The two most common additional costs are a higher monthly interest rate and a per-month extension fee. Both are applied on top of the ongoing interest that continues to accrue on the balance.

The rate uplift during an extension varies by lender but 0.25% to 0.50% above the original rate is common. On a £300,000 facility, a 0.25% uplift adds £750 per month of extension in additional interest. The extension fee is typically calculated as a percentage of the gross loan (commonly 1%), charged for each month of extension. On a £300,000 loan, that is £3,000 per extension month. Together, a single month of extension on this facility could cost approximately £3,750 above what each month during the planned term cost. The extensions vs refinancing guide covers the decision between extending and finding an alternative exit when the original plan does not land on time.

The daily cost of delay

Bridging loans are priced monthly, but delays are measured in days and weeks. A refurbishment project that overruns by two weeks, a sale that is delayed by a solicitor’s holiday, a refinance valuation that takes an extra week to book: these are all real-world scenarios where the cost is incurred in days, not months. The daily cost figure translates the monthly pricing into the metric that matters for project management and completion planning.

During the extension period, the daily cost is typically higher than during the planned term because the extension rate may be higher and extension fees add a fixed cost per month. A facility that costs £80 per day during the planned term might cost £160 per day during an extension once the rate uplift and fees are included. Knowing both figures before agreeing the facility allows the borrower to build realistic contingency into the project budget rather than discovering the daily cost of delay at the point when it is already being incurred. The common causes of refurbishment delay guide covers the practical factors that most frequently push exits beyond the planned term.

Building a buffer into the original term

The most effective way to avoid extension costs is to set a realistic original term. A term that covers the exit timeline plus one to two months of buffer ensures that a modest delay does not trigger extension fees and rate increases. The cost of the buffer months is the additional retained interest deducted (for retained structures) or the additional compounding on the balance (for rolled-up structures). In most cases, this is materially cheaper than the equivalent extension cost.

The tool quantifies this trade-off directly. The planned cost column shows the total cost at the chosen term, including any buffer months. The extension column shows what happens if the buffer is not sufficient and an extension is needed. Comparing the two makes the insurance value of the buffer visible. The early exit modeller complements this by showing the cost saving if the exit comes earlier than the buffered term, which quantifies the upside of the buffer: if it is not needed, the borrower exits early and pays less.

Related tools

Early exit

Early exit modeller

Shows the cost of exiting a bridge at any month before the full term, including minimum interest periods and retained rebate modelling. Use it alongside the delay calculator to see the full cost curve from earliest exit to latest extension. Use the tool

Quote comparison

Bridging loan quote comparator

If two lenders offer different extension terms, model the extension cost for each in this tool, then compare the full-term and extension costs side by side in the comparator. Use the tool

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Frequently asked questions

Do all bridging lenders offer extensions, or can they refuse?

Lenders are not obligated to offer an extension. Most will consider one if the borrower communicates proactively, the exit strategy remains credible, and the LTV position has not deteriorated. A borrower who approaches the lender with evidence of a delayed but realistic exit, such as a sale agreed but not yet completed or a refinance application in progress, is in a much stronger position than one who simply runs out of term with no plan. Some loan agreements include pre-agreed extension terms, which provide certainty about the cost and availability of an extension before it is needed.

If a lender declines to extend, the borrower may need to refinance the bridge with another lender (a “re-bridge”), which involves its own arrangement fees, legal costs, and a potentially higher rate. The cost of a re-bridge is typically significantly higher than a formal extension, which is another reason to choose the original term with a realistic buffer rather than the minimum possible duration.

What is a typical extension fee in the UK bridging market?

Extension fees commonly range from 0.5% to 1.5% of the gross loan per month of extension, with 1% being the most frequently quoted figure. On a £300,000 gross loan, a 1% extension fee is £3,000 per month. This is charged in addition to the ongoing interest, not instead of it. Some lenders charge a flat fee per extension rather than a percentage, and a small number include extension terms in the original offer without additional fees (though typically at a higher rate). Confirming the extension terms before agreeing the facility is one of the most important questions to ask during the quote comparison stage.

The bridging loan fees guide covers extension fees alongside the full cost structure including arrangement fees, exit fees, and other charges.

Why is the daily cost higher during the extension than during the planned term?

Two factors typically combine to make the extension period more expensive per day. First, many lenders charge a higher monthly rate during extensions, often 0.25% to 0.50% above the original rate, reflecting the increased risk of a facility that has not exited as planned. Second, extension fees add a fixed cost per month on top of the ongoing interest. The daily cost during the planned term includes only the interest and the amortised arrangement fee. The daily cost during the extension includes those plus the rate uplift and the extension fee, which together can double the daily cost compared to the planned period.

For rolled-up interest structures, there is a third factor: by the time the extension begins, the interest that has been compounding during the planned term has increased the outstanding balance, so even at the same rate the monthly interest amount is higher. The tool accounts for this by calculating the extension interest on the balance at the end of the planned term rather than on the original loan amount.

How much buffer should I add to the planned term?

There is no single answer because the appropriate buffer depends on the exit strategy and its complexity. For a chain-break where the sale is already agreed, one to two months may be sufficient. For a refurbishment and sale where works could overrun and the sale process has not yet started, two to three months is more prudent. For a refinance exit that depends on the property reaching a specific condition, the buffer needs to account for both the works timeline and the refinance application timeline.

The tool helps quantify the cost of the buffer. Adding two months to a 9-month term makes it an 11-month facility. The additional retained interest or rolled-up compounding for those two months is the “insurance premium” for avoiding an extension. If the exit lands on time at month 9, the early exit modeller shows the saving from exiting before the full buffered term. In most cases, the buffer cost is a fraction of what a formal extension with fees and rate uplift would cost.

What happens if the lender charges default interest instead of offering a formal extension?

Default interest is a penalty rate applied when the facility has expired without redemption and the borrower has not agreed a formal extension. Default rates vary but are typically significantly higher than the contractual rate, sometimes 2% to 4% per month or more. This is a punitive mechanism designed to incentivise prompt exit, and the cost can escalate rapidly. On a £300,000 facility, default interest at 3% per month is £9,000 per month, which is more than three times the cost of a typical 1% rate during the planned term.

Avoiding default interest requires proactive communication with the lender before the term expires. If the exit is delayed, approaching the lender with a revised timeline and evidence of progress (sale listing, refinance application, works completion evidence) is far more likely to result in a negotiated extension at manageable terms than waiting until the term has already expired. The guide on strong exit strategies covers how to structure the exit plan in a way that minimises the risk of default.

Squaring Up

The cost of a bridging loan extension is almost always higher per month than the cost during the planned term, because the rate may increase and extension fees add a fixed cost on top. The daily cost metric translates these monthly figures into the per-day and per-week costs that matter for project planning and completion meetings. Knowing both the planned daily cost and the extension daily cost before agreeing the facility turns a “what if the exit is late” question into a quantified risk rather than an unpriced uncertainty.

The most effective defence against extension costs is a realistic original term with a built-in buffer. The cost of one or two extra months of retained interest or rolled-up compounding is typically a fraction of the extension fees and rate uplift that would apply if those months are needed as a formal extension. This tool quantifies both sides of that calculation.

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This tool is for illustrative purposes only and does not constitute financial advice. Extension terms, rates, and fees vary between lenders and are subject to the lender’s discretion and the borrower’s circumstances. Some lenders may decline to offer an extension. Default interest rates apply if the facility expires without redemption or a negotiated extension. Your property may be repossessed if you do not keep up repayments on a bridging loan. Actual outcomes will depend on your individual circumstances.

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