Council Tax Letters

Boosting council tax repayments with behavioural nudges

How could we encourage customers to pay their council tax arrears and avoid legal action with a very low cost intervention?

Overview

Council tax arrears are one of the largest drivers of avoidable legal enforcement within local authorities, creating significant cost for organisations and stress for customers. Many customers fall into debt not because they refuse to pay, but because communications are confusing, emotionally loaded, and difficult to act on.

This project focused on redesigning council tax reminder and final notice letters to improve payment behaviour and reduce escalation to legal action, using behavioural insight and service design to increase clarity, trust, and actionability.

Impact:

~17% reduction in progression to court summons
Increased timely repayment of council tax
Reduced enforcement and legal processing costs
Evidence base to support wider debt service transformation

My role

Service Design Lead

I led the end-to-end design, behavioural framing, and evaluation of the intervention. This included:

Framing the problem and success metrics
Leading journey mapping and process analysis
Applying behavioural insight to communication design
Working with service, data, and legal teams to ensure viability
Designing the evaluation approach and interpreting results
Translating findings into recommendations for scale

The problem

Council tax communications play a critical role in how customers understand their obligations and options. However, existing reminder and final notice letters:

were dense, legalistic, and hard to navigate
lacked clear calls to action
escalated quickly to enforcement without supporting customers to respond

This resulted in:

high progression to court summons
increased costs for the organisation
worse outcomes for customers, particularly those already under financial stress

Context and constraints

This work took place in a highly regulated, high-stakes environment:

Communications are legally prescribed and cannot be changed arbitrarily
Council tax affects a large, diverse population with varying levels of digital access
Decisions had to be defensible, auditable, and scalable
There was limited scope for direct user research within the timeline

Any change needed to be low-risk, evidence-led, and operationally viable.

Discovery and insight

We mapped the end-to-end council tax arrears journey, combining:

process walkthroughs with service teams
analysis of escalation and repayment data
detailed review of existing communications and decision points

Key insights included:

Customers often did not understand what to do next or how urgent the situation was
Calls to action were buried or ambiguous
The tone of letters increased anxiety, leading to avoidance rather than action
Small points of friction (finding payment details, knowing who to contact) compounded delay

These insights suggested that clarity and ease of action, rather than enforcement intensity, were the biggest levers for change.

Hypothesis

If council tax communications clearly prioritise the required action, reduce cognitive load, and make payment or support easier to access, then more customers will pay earlier in the journey, reducing escalation to court summons.

Design approach

Given the constraints, we focused on behaviourally informed communication changes that could be implemented quickly and safely.

Key design decisions included:

Clear prioritisation of the primary action (what the customer needs to do now)
Simplified structure and language to reduce cognitive load
Improved signposting to payment and support options
Tone changes to reduce threat-based messaging and increase perceived support

The goal was not to “soften” enforcement, but to make the path to compliance clearer and easier.

Evaluation

We evaluated the redesigned reminder and final notice letters by measuring their effect on payment behaviour and enforcement escalation.

Primary metric:

Percentage of cases progressing from Reminder / Final Notice to Court Summons

In the council tax journey, progression to court summons occurs only when payment has not been made at any prior stage (bill, reminder, or final notice). A summons marks the start of formal enforcement and legal action, creating additional cost and risk for both the organisation and the customer.

The redesigned reminder and final notice letters have been live in production since November 2023. We analysed outcomes across thousands of council tax letters sent between July 2023 and March 2024, allowing comparison of pre- and post-intervention performance.

Baseline (pre-intervention):

July–October 2023: ~23% of cases progressed to court summons

Post-intervention:

December 2023–March 2024: ~19% of cases progressed to court summons

Result:

~17% reduction in progression to court summons following the redesigned communications

This indicates that a greater proportion of customers paid or engaged earlier in the journey, preventing escalation into legal enforcement.

Impact and outcomes

Improved timely repayment, protecting council tax revenue
Reduced initiation of legal enforcement, avoiding summons and follow-on recovery costs
Lower harm to customers, who avoided fees, legal action, and associated stress
Reduced operational burden across revenues, legal, and customer service team

By improving clarity and actionability at key decision points, the intervention shifted behaviour upstream - increasing repayment while reducing downstream cost and risk.

Learnings

The behavioural approach can rapidly generate viable interventions in the absence of traditional user research when grounded in evidence.
Small communication changes can unlock disproportionate impact when applied at scale.
Rigorous evaluation is essential to build trust and momentum for wider transformation.
Designing for compliance and care does not have to be a trade-off.