Proportionality in costs remains one of the most frequently cited principles in civil litigation. Embedded within CPR 44.3, it requires that recoverable costs bear a reasonable relationship to the matters in issue. In theory, it acts as a safeguard against excessive expenditure.

In practice, however, the court’s approach to proportionality is far less predictable. While it is routinely invoked, its impact varies significantly depending on the case, the judge, and the stage at which it is applied.

This raises an increasingly familiar concern: is proportionality functioning as a meaningful control on costs, or has it become a tool applied retrospectively to justify reductions after the event?

 

The Framework Under CPR 44.3

CPR 44.3 sets out the proportionality test, requiring the court to consider whether costs are proportionate, having regard to a range of factors. These include:

• the value of any monetary relief
• the complexity of the litigation
• the conduct of the paying party and receiving party
• any additional work generated by that conduct
• wider factors such as reputation or public importance

Importantly, the rule makes clear that even where costs are reasonably incurred, they may still be reduced if they do not meet the requirement of proportionate cost.

This establishes a distinction between reasonableness and proportionality, although in practice the boundary between the two is not always clearly maintained.

 

Rigorous Application of Proportionality in Costs Law

There are instances where the court adopts a firm and structured approach to proportionality, particularly at the stage of detailed assessments.

In these cases, a costs judge may step back from a purely line-by-line assessment and instead consider whether the total level of the claimant’s costs is justified in the context of the case as a whole. Where the figure is considered excessive, reductions may be made even if individual items were reasonably incurred.

This is often seen in cases where:

• Costs significantly exceed the value of the claim
• The litigation has not justified the level of resources deployed
• There is a disconnect between the issues and the overall spend

In such circumstances, proportionality operates as a broad control mechanism, allowing the court to reduce costs globally.

 

When Proportionality Appears Secondary

In other cases, however, proportionality appears to recede into the background.

Where the complexity of the litigation is high or where costs have been driven by the conduct of the parties, the court may be more inclined to focus on whether the work was necessary and reasonable. This is particularly so where additional work has been generated by the conduct of one party, which may justify higher levels of expenditure.

Similarly, where costs have been incurred in line with costs budgets approved by the court, there may be less appetite to revisit the overall level of costs at the end of the case. While budgets do not displace proportionality entirely, they can influence how it is applied in practice.

The result is a degree of inconsistency. Proportionality is always present, but not always decisive.

 

The Role of Detailed Assessment

The relationship between proportionality and detailed assessment is central to understanding its practical effect.

While the process is structured around a line-by-line assessment, proportionality often emerges as a separate, overarching consideration. After reviewing individual items, the court may take a step back and consider whether the total figure is proportionate.

This can give the impression that proportionality is being applied as a final adjustment, rather than as a guiding principle throughout the litigation. For the receiving party, this introduces a level of risk: costs that appear reasonable in isolation may still be reduced when viewed in aggregate.

 

The Influence of Conduct

The conduct of the paying party and receiving party remains a key factor in the court’s analysis.

Where one party’s behaviour has driven the scope or complexity of the litigation, the court may be more willing to allow higher costs on the basis that they were reasonably incurred in response. Conversely, where costs have been inflated by inefficiency or duplication, reductions are more likely.

This reinforces the idea that proportionality is not applied in isolation, but as part of a broader evaluative exercise that takes into account how the litigation has been conducted overall.

 

Is Proportionality Predictable?

One of the most persistent criticisms of proportionality is its lack of predictability.

Although CPR 44.3 provides a framework, its application is inherently fact sensitive. Two cases with similar values may produce very different outcomes depending on factors such as complexity, conduct, and the importance of the issues at stake.

The Court of Appeal has offered guidance on proportionality in a number of cases, but this has not eliminated uncertainty. Instead, it has reinforced the need for a contextual approach.

For practitioners, this makes it difficult to assess risk with confidence, particularly in cases where costs are likely to be significant.

 

A Principle Applied in the Round

It may be more accurate to view proportionality not as a strict rule, but as a principle applied “in the round.”

Rather than operating as a precise calculation, it allows the court to stand back and consider whether the overall level of recoverable costs is justified. This explains why it can appear to operate inconsistently: its application depends on the court’s assessment of the case as a whole.

In that sense, proportionality is less about precision and more about control.

Practical Implications for Litigators

For practitioners, the key point is that proportionality cannot be treated as an afterthought.

Even where work is necessary and reasonable, there remains a risk that costs will be reduced if they do not bear a reasonable relationship to the matters in issue.

This means that:

• costs should be considered strategically throughout the case
• The potential for reduction at detailed assessment should be factored in early
• The conduct of both parties can materially affect recoverability
• Reliance on costs budgets alone may not provide complete protection

Ultimately, proportionality continues to shape outcomes, even if its application is not always consistent.

 

How Greener Costs Can Assist

Proportionality remains one of the most challenging aspects of costs recovery, particularly in complex or high-value litigation.

Greener Costs provides specialist advice on all aspects of detailed assessments, proportionality challenges, and strategic costs management. By addressing proportionality issues early, it is possible to reduce uncertainty and improve the prospects of recovering costs in full.

If you require assistance, contact Greener Costs today:

📞 01204 263047
📧 info@greenercosts.co.uk

 

Frequently Asked Questions

What is the proportionality test under CPR 44.3?

It requires that recoverable costs bear a reasonable relationship to the matters in issue, taking into account value, complexity, conduct, and wider factors.

Can reasonable costs still be reduced?

Yes, even where costs are reasonably incurred, they may be reduced if they are considered disproportionate overall.

How is proportionality applied in detailed assessments?

While individual items are assessed line by line, the court may step back and consider whether the total figure is proportionate.

Does conduct affect proportionality?

Yes, costs generated by the conduct of the paying party or receiving party can influence whether costs are considered proportionate.