A Market Fall During a Portfolio-Backed Loan: Stress-Testing Margin Calls and Liquidity

Market Value and Lending Value Are Different Figures

A portfolio-backed lender assesses eligible assets and assigns lending values to them. Those values determine how much borrowing the collateral can support under the facility’s terms.

The lender may apply different advance percentages to different holdings. Some assets may receive no lending value. Currency, liquidity, concentration and the characteristics of the investments can all be relevant to that assessment.

UBS’s published Lombard explanation describes lending values that are reviewed and may change, alongside the requirement to provide further collateral or reduce borrowing when security becomes insufficient. Its specific product terms relate to a Swiss offering; the relevant requirements for a client must come from their own lender. Read the explanation of lending values and collateral risk.

A useful lending stress test therefore starts with the actual facility: the assets accepted, the values assigned, the outstanding obligations and the contractual trigger for action. Applying a market-fall percentage to the portfolio alone does not answer the full question.

A Worked Example: £400,000 Borrowed Against a £1 Million Portfolio

Consider a simplified portfolio-backed facility used to fund a property purchase. The figures below are hypothetical and do not describe a current lender quotation.

Initially, the £1 million portfolio supports £500,000 of debt. Against the £400,000 drawn, that leaves £100,000 of collateral headroom under the assumed calculation. It is not a separate cash reserve or a promise that further borrowing will remain available.

After a 20% Fall

The portfolio is worth £800,000. At the unchanged 50% lending value, it supports £400,000 of debt.

The original headroom has been exhausted. The loan is exactly at the assumed ceiling. Any further decline, added borrowing or relevant charge would create a shortfall in this simplified model.

After a 30% Fall

The portfolio is worth £700,000. At 50%, it supports £350,000 of debt. The outstanding £400,000 now exceeds the lending value by £50,000.

Real facilities may have separate warning levels, maintenance thresholds, concentration limits and required restoration buffers. A lender may require more than simply returning to the initial trigger point. The illustration does not establish the actual amount or time allowed under any particular facility.

Cash Repayment, Additional Collateral and Asset Sales Work Differently

A £50,000 collateral shortfall does not necessarily mean that selling £50,000 of pledged investments will resolve it. The result depends on where the money comes from and what remains as security.

Repaying £50,000 From External Cash

In the 30% fall scenario, a £50,000 repayment from cash held outside the pledged portfolio reduces the loan to £350,000. The £700,000 portfolio remains intact as collateral and, at the assumed 50% lending value, supports that balance.

Providing Additional Eligible Collateral

If the borrower instead adds investments that also receive a 50% lending value, they would need £100,000 of additional market value to create £50,000 of lending value. The lender must accept the assets and complete the required security arrangements.

The amount would differ if the additional collateral received another lending percentage. Cash pledged as security should also be distinguished from cash used to repay debt; its treatment depends on the facility.

Selling Assets Already Inside the Pledged Portfolio

If £50,000 of the pledged investments is sold and all proceeds repay the loan, the debt falls to £350,000—but the portfolio falls to £650,000. At 50%, the remaining collateral supports only £325,000. A shortfall remains.

Under the same simplified assumptions, selling £100,000 of pledged assets and applying all proceeds to repayment leaves a £600,000 portfolio and £300,000 of debt. The two are then aligned at the assumed 50% ceiling.

These calculations assume unchanged prices during execution, identical lending percentages and no dealing costs or taxes. Actual outcomes depend on which assets are sold, their lending values, settlement and the lender’s requirements. This is an explanation of the loan mechanics, not a recommendation to sell particular investments.

Test Changes to the Lending Terms as Well as Market Prices

A single market-fall scenario may miss another source of pressure: a change in how the lender values the collateral for lending.

Returning to the example, suppose the portfolio falls by 20% to £800,000 and the assumed advance percentage is reduced from 50% to 40%. It would then support £320,000 of debt, leaving an £80,000 shortfall against the £400,000 loan.

This is a separate hypothetical scenario. It illustrates the effect of two inputs changing together, rather than suggesting that lenders apply a standard reduction during every market fall.

Coutts’ published risk information specifically identifies insufficient security and certain currency movements as possible causes of a margin call. Read the lender’s margin-call explanation.

The investment adviser determines appropriate portfolio scenarios within their remit. Willow can help establish how the proposed lender’s rules translate those scenarios into funding requirements.

Test Whether the Required Funds Would Actually Be Available

Identifying a potential shortfall is only the first part of the lending exercise. The next question is whether the client can produce the required cash or acceptable collateral by the deadline.

Funds that have already been spent on a property purchase cannot also be counted as an available reserve. Nor should the unused portion of a portfolio-backed limit be assumed to remain drawable when the same collateral has fallen in value.

These are practical availability questions. The wider decision about how much liquidity the client should retain belongs within their financial planning. The lender’s immediate requirement still needs to be matched to resources that can actually be delivered.

The Response Period Can Be as Important as the Amount

Do not assume that every lender gives the same notice or allows a standard number of days to correct a shortfall. The agreement and the lender’s actual notice govern what is required.

Before drawdown, establish who receives collateral notices, how the borrower is contacted and who is authorised to arrange a repayment or transfer. Where the client has consented, the relevant advisers should understand the communication process.

If a call occurs, obtain the lender’s current calculation, the required action, the deadline and confirmation of the remedies it will accept. A request for more time should not be treated as agreed unless the lender confirms it.

Settlement, bank cut-off times, custody transfers and cross-border arrangements can affect delivery. A transaction instructed before a deadline may still fail to provide cleared funds or perfected security in time.

Depending on the facility, failure to meet the requirement can allow the lender to sell pledged assets. The amount realised may be insufficient to discharge all the debt. Legal advisers should address the contractual enforcement provisions where interpretation is required.

Where Property Finance Can Fit—and Why Timing Matters

If the borrowing funds a property purchase, it can be useful to assess mortgage options before the portfolio-backed facility is drawn. That establishes whether property security could support some or all of the funding and what the alternative commitment would involve.

Once a margin call has arrived, a new mortgage should not be assumed to provide an immediate solution. The borrower and property still need to meet lender criteria, and approval, valuation, legal work and drawdown conditions must be completed.

Short-term property finance also requires assessment. Speed is only useful where the facility can be delivered, the costs are understood and the repayment route is credible. Replacing a collateral shortfall with another borrowing commitment does not remove the need for an exit.

A conventional residential mortgage secured only on property does not normally create a margin call because an unrelated investment portfolio falls. It has its own repayment obligations, repossession risk and refinancing constraints. Commercial and other specialist property facilities may include additional covenants that need separate review.

Willow can compare the credible property-finance routes and explain their availability, costs and timescales. We cannot guarantee an emergency refinance or that a lender will extend a collateral-call deadline.

When to Involve Willow

The most useful point is often before the client commits assets as security. If the proposed borrowing is intended to fund property, Willow can help establish whether a mortgage or another property-backed route is available alongside the portfolio-backed proposal.

An early discussion is particularly worthwhile where the purchase would absorb most of the client’s available cash, the planned response to a margin call involves new borrowing, or the repayment strategy depends on a future property transaction.

We can begin with an anonymous outline of the property, approximate value, funding requirement, timing, existing borrowing and principal concern. Detailed portfolio statements or client-identifying documents are not needed for that initial conversation.