References to LIBOR in late payment clauses: mind the gap

References to LIBOR in late payment clauses: mind the gap

This briefing was first published on 3 March 2021 and updated on 14 March 2023. 


For many years, late payment clauses in commercial contracts referred to LIBOR as a proxy for the cost of money over time and a hedge against inflation. But do you understand what was meant by "LIBOR"? Did you know that the rate was recently discontinued and is now being published on a synthetic basis for a limited period? How will this impact on the drafting of new late payment clauses (or construing clauses in existing contracts which include a reference to this rate)?

What is LIBOR?

The London Inter-Bank Offered Rate (LIBOR) was a reference rate of interest used historically in a vast number of financial contracts including cash products (such as loans, bonds and other debt securities) and derivatives transactions.

It was an interbank interest rate calculated using data from a number of panel banks active in the London financial markets, representing a rate at which (theoretically at least) those banks were prepared to lend to one another.

Parties to commercial contracts used "LIBOR" as a proxy for the cost of tying up money over time. To refer simply to "LIBOR" without further precision was very ambiguous. In fact LIBOR (further explained here) was, until recently, quoted as an annualised interest rate for five currencies (USD, GBP, EUR, CHF, JPY) and also for a range of (forward looking) tenors. So for instance the sterling LIBOR rate for three months would have been different to a dollar LIBOR overnight rate.

Cessation of LIBOR - what next?

LIBOR came under increased public scrutiny after the LIBOR scandals of 2007-12, which centred upon the alleged manipulation of the rate by panel banks for their own ends.

After a comprehensive review of LIBOR, and whether it remains fit for purpose, the Financial Conduct Authority (FCA) announced in 2017 that market participants should not rely on LIBOR being available after 31 December 2021. The Bank of England (BoE) and the FCA remained committed to this deadline despite COVID-19 and since the beginning of 2022, sterling LIBOR has only been quoted for a limited number of settings, for the most part on a synthetic basis (no longer relying on submissions from panel banks). "Synthetic LIBOR" for sterling will now only be available for a limited period.

  • The 1- and 6-month synthetic sterling LIBOR settings will cease at end-March 2023.
  • The 3-month synthetic sterling LIBOR setting will cease at end-March 2024.

SONIA: not an exact replacement of LIBOR

It is important to understand that sterling "synthetic LIBOR" will not be available in any form after 31 March 2024 (see the FCA announcement here). Hence disputes could arise where a contract referring to LIBOR remains in force after the rate is discontinued.

Central bank working groups have been working to facilitate transition for different currencies. For sterling lending, the Bank of England Working Group's proposed successor rate is SONIA (the Sterling Overnight Index Average). There are crucial differences between the two rates:

  • LIBOR was a forward looking term rate, reflecting the price at which banks were prepared to lend to each other for a given period (3 months being the most widely used interest period). It therefore featured a bank credit risk component, which caused LIBOR rates to spike during the 2008 financial crisis.

  • SONIA is a backwards looking overnight rate; a measure of the rate at which interest is paid on sterling short-term wholesale funds in circumstances where credit, liquidity and other risks are minimal. Consequently SONIA is usually a lower rate than LIBOR.

Accordingly, during the course of a day, it was possible to find out the LIBOR number for the next three months. The same cannot be said for SONIA, which is a different number every business day.

Late payment clauses - a reminder

Late payment clauses will typically impose an agreed interest rate on the late payer in order to compensate the creditor, who may have to fund its own related expenses. There is also a deterrent element here; the prospect of a late payment fee is a 'stick' to deter late payment, although care should be taken not to set the rate so high that it could be regarded as a penalty – see section 5 (Drafting pitfalls).

Floating and fixed rate elements

Late payment clauses frequently comprise a floating rate element which serves as a "base" (e.g. a commercial or central bank base rate or other specified benchmark rate), plus a fixed rate "uplift" (X per cent. per annum). The floating rate (e.g. until recently, three month sterling LIBOR) is designed to hedge against inflation. A decade ago, LIBOR exceeded 5 per cent. and so it served as a substantial tool to help creditors cover their cost of funds. During the low interest environment which prevailed until 2022, the floating rate element of the equation made little difference to the overall late payment amount; the "stick" to deter late payment was really that X per cent. uplift. More recently SONIA has stepped up in line with base rates and, as at March 2023, the SONIA overnight rate is currently hovering around 4 per cent.

The statutory interest rate

It's important, however, to remember the default position for creditors in commercial contracts if the documentation is silent on consequences of late payment. Under the Late Payment of Commercial Debts (Interest) Act 1998 (the "Late Payment Act"), a term will be implied into contracts for the supply of goods or services enabling interest to be claimed on late payments at a statutory rate, currently consisting of the Bank of England base rate plus 8 per cent.  This rate has not been changed since 2002 and may appear generous given current low rates of commercial interest.  The implied term can, however, be displaced if the contract provides for "some other substantial contractual remedy" for late payment.

What is a substantial remedy?

There is limited caselaw on what constitutes a "substantial remedy"; however, in practice, the courts have found an interest rate of 5 per cent. above the base rate of a commercial bank was sufficient and have accepted that a case could also be made for 3-4 per cent. above base. For customers, therefore, it is obviously desirable to replace the implied statutory rate with a less generous, express remedy. Although it is arguably to the benefit of suppliers for their contracts to remain silent on late payment (so that the statutory rate will apply), in practice it is also fairly common for suppliers' standard terms to provide for an express remedy at a lower rate (perhaps reflecting a concern that some customers may view the statutory rate as excessive). For a more detailed discussion of the Late Payment Act, see our briefing "Late payment clauses: time for a review?"

Other developments

The UK Government had hoped that the Late Payment Act would help to promote a culture of prompt payment but in practice, problems with late payment persist. In particular, suppliers are often understandably reluctant to claim late payment interest from their customers (even where they would be legally well within their rights to do so). More recently, the Government has taken a number of other steps intended to discourage late payment including:

  • measures requiring all large UK companies and LLPs to publish information on their payment practices and performance twice a year (see our related briefing here); and
  • consulting on strengthening the powers of the Small Business Commissioner to enable them to impose fines on businesses which fail to pay smaller businesses on time (see our briefing here).

In December 2022, the Government announced a Payment and Cashflow Review which will look again at the existing measures, alongside other ways in which business (particularly SMEs) could be supported in managing cashflow such as use of technology, finance and improving awareness. For more detail, see our briefing "Late payment clauses: time for a review?" 


What rate could be used to replace LIBOR in late payment clauses?

In view of the LIBOR wind-down, parties will need to settle on a substitute rate. SONIA is likely to be a component of the replacement rate for LIBOR in sterling loan markets, particularly for loans with sufficient scale. However, there are issues which in our view make SONIA somewhat problematic as a candidate to replace LIBOR in late payment clauses.  For example, when using SONIA to calculate interest over a longer period there are several options.

  • The daily overnight rate could be "compounded", which gives rise to complex calculations (a necessary feature in large scale commercial lending, but unattractive for late payment clauses).

  • Parties might use the rate quoted on a given reference day, e.g. the first day of the 'late' period or on the first day of a calendar month, which could lead to unpredictable results when there are spikes in the daily overnight rate.

  • A middle ground might be to use a simple average of SONIA for the period during which amounts are outstanding. This would avoid the potential volatility of using a single reference date. However the rate would only be able to be calculated at the end of the period.

A complicating factor is that the daily SONIA rate is quoted to four decimal places (see the Bank of England statistics at the bottom of the page here). One alternative would be to use "Term SONIA" instead of sterling LIBOR. This rate has the advantage of being known at the beginning of the relevant period (like LIBOR). Indeed, Term SONIA is a key ingredient of the so called "synthetic LIBOR" rate which the FCA has required to be published for a limited period (see section 2). The £RFR Working Group has published a summary of the key attributes of the various competing Term SONIA Reference Rates here.

Term SONIA and Term SOFR

Parties may consider using Term SONIA (for sterling) or Term SOFR (for dollars) as a LIBOR replacement.

Term SONIA is a forward-looking term rate derived from executable quotes for SONIA-based interest rate swaps. Put simply, it is a prediction of how the daily overnight SONIA rate might perform over a future period (e.g. 3 months). It is published by benchmark administrators including Refinitiv and ICE, also made available through a range of familiar distribution platforms. UK regulators are keen to ensure that financial institutions do not use Term SONIA for mainstream bank lending, outside certain limited use cases. However there is no such restriction on other commercial parties using this rate.

Term SOFR, the dollar rate, is a daily set of forward-looking interest rate estimates of future movements in the Secured Overnight Financing Rate, calculated and published by the Federal Reserve Bank of New York. It is eligible for use in general business loans (in contrast to the much narrower use cases for £ Term SONIA).

Central bank rates

Parties to a contract may find it easier to substitute a central bank rate into the late payment equation and the result would be substantially the same, with the creditor retaining some hedge against inflation and/or cost of funds. Another factor to consider is that central bank rates tend to remain the same for months at a time and are usually quoted as a round number. Indeed, SONIA typically tracks the Bank of England Bank Rate very closely and is likely to result in a similar outcome (although SONIA tends to be fractionally lower).

In view of these factors, parties may conclude that it is preferable to replace LIBOR with a central bank rate. The choice may depend on where the parties are located or the currency used in the contract.

Drafting pitfalls

As noted in the discussion of SONIA above, ease of calculation is an important factor when drafting a late payment clause. Think of the person running the calculations! A well drafted clause only requires the creditor to locate the reference rate once (or infrequently). For instance, a clause might refer to the rate quoted on the first day of the 'late' period or on the first day of a particular calendar month. A pitfall to avoid would be to refer to a rate which changes daily (e.g. simple SONIA) and to require the rate to be calculated daily.

Another consideration is the ease with which the rate can be found. A rate which is readily verifiable will help to avoid disputes.

Negative interest rates

In the case of reference to central bank rates, a complicating factor (until recently) was the spectre of negative interest rates. If the late payment rate factors in a large enough level of uplift (based on a fixed rate), then a negative central bank rate of -0.10% might make little commercial difference to the outcome. In the current inflationary environment, parties may be less concerned about this risk. Nevertheless, it will help to clarify whether, in calculating the rate, negative rates should be ignored (i.e. if negative, the base rate should simply be regarded as zero and the late payment interest will consist solely of the fixed rate "uplift").

Penalty clauses

Finally, it is important to ensure that the late payment interest rate is not set at a level which could be regarded as penal (and therefore unenforceable).  It is highly unlikely that a rate set at or below the statutory rate of Bank of England base rate plus 8 per cent would be regarded as penal, even though this may appear generous by comparison with current commercial lending rates.  In addition, recent caselaw on penalty clauses suggests that it is permissible to have regard to the need for a deterrent effect, not just the need to compensate the innocent party for its potential loss – see our related briefing here. That said, the clause must not be "exorbitant or unconscionable" – see textbox below for an example.

What is a penal rate of interest?

In Jeancharm v Barnet (2003), late payment interest of 5 per cent per week (rather than per annum) was found to be penal.  Although the test for penalty clauses has since been modified by the Supreme Court, our view is that a rate equating to over 200 per cent. per annum remains likely to be regarded as penal, even under the revised test.  This case also highlights the importance of ensuring that it is clear how late payment interest is to be calculated.  On the face of it, 5 per cent. sounds reasonable - but when applied on a weekly basis, it involves substantially higher sums than most late payment rates, including the statutory rate (which are calculated on a yearly basis).

What if a late payment clause using LIBOR has not been amended?

As explained in section 2 above, since the beginning of 2022 the 3, 6, and 12 month LIBOR tenors have been published on a synthetic basis. For contracts entered into prior to 1 January 2022, the Critical Benchmarks (References and Administrators' Liability) Act 2021 provides that a reference in "a contract or other arrangement" to LIBOR will be construed as a reference to synthetic LIBOR. In most cases this will override any express contractual fallbacks that would otherwise have operated on cessation of LIBOR. Essentially, the contract will be treated as if it had always provided for the reference to include the synthetic benchmark.

The FCA has announced that it will not require publication of synthetic LIBOR for the 6 and 12 month settings after 31 March 2023, and for the 3-month setting after 31 March 2024. For contracts made on or after 1 January 2022 or for any contract still in force after the relevant synthetic sterling LIBOR setting ceases to be published, the situation will be more complex. Thereafter, if a clause has not been amended so as to substitute an alternative rate, the courts will need to reach a view on what the parties would have intended to happen in this situation. Their starting position may well be that the parties must have intended a late payment remedy to apply and therefore the key question is whether it is possible to infer what should replace LIBOR. However, as noted above, this is not a straightforward question to resolve.  For example, SONIA is not an exact replacement for LIBOR and its use as a substitute may simply give rise to further disputes over how the interest should be calculated.

In view of these complexities, there is a risk that in some cases, a court could conclude that it is unclear what the parties intended – and that either the statutory rate should apply (which effectively favours the supplier) or there should be no remedy at all (on the basis that, as the clause was primarily intended to protect the supplier, the onus was on the latter to ensure that it was updated to deal with the consequences of LIBOR cessation).

How Travers Smith can help you

Given that LIBOR will soon be unavailable (even on a synthetic basis), our recommendation is to amend any late payment clauses using LIBOR, both in existing contracts and in any standard "boilerplate" that will be used for future contracts. This should avoid uncertainty and unnecessary disputes over what the parties intended. Solutions may vary depending on factors such as the currency used in the contract and the location of the parties.

We have advised a number of clients on this issue and can help you work out the best options for your business going forward.  If you are reviewing boilerplate/standard terms, there may also be other changes that you will wish to consider alongside LIBOR cessation, such as:

LIBOR - our wider experience

As regards LIBOR cessation more generally, we have extensive experience in advising clients on LIBOR impact assessment and transition plans.  Our close relationships with industry bodies such as ISDA, ICMA, the LMA, AIMA and BVCA mean that we are well placed to advise you on what needs to be done to amend contracts to incorporate LIBOR fallback mechanics.


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