ISO 10002:2018 is the third edition of ISO’s guidelines for complaints handling in organisations. It was published in July 2018, and the standard’s page states that it was reviewed and confirmed in 2023 and remains current. It gives guidance on handling complaints about an organisation’s products and services, covering the whole process from planning and design to operation, maintenance and improvement, and applies to any organisation regardless of type or size, with an annex for small businesses. ^[1]

The standard does not cover disputes referred to external bodies or employment-related disputes. ^[1] It is compatible with ISO 9001 and ISO 9004 and can be used on its own or as an element of a quality management system. It sits alongside three sister standards, whose relationship is set out in its Annex A: ISO 10001 for codes of conduct, ISO 10003 for dispute resolution external to the organisation, and ISO 10004 for monitoring and measuring customer satisfaction. ^{[2, 6]}

The standard defines a complaint as an expression of dissatisfaction made to an organisation about its product or service, or about the complaints-handling process itself, where a response or resolution is explicitly or implicitly expected. ^[2] So an angry post on social media can be a complaint even if it never went through the official form.

The principles that govern the process

Clause 4 sets out fourteen guiding principles (4.2 to 4.15): commitment, capacity (sufficient resources), transparency, accessibility, responsiveness, objectivity, charges, information integrity, confidentiality, a customer-focused approach, accountability, improvement, competence and timeliness. ^[2]

The most important in practice:

• Transparency: communicate the complaints process to customers, staff and other interested parties, and keep each complainant informed about how their complaint is being handled. ^[2]
• Accessibility: the process should be easy for every complainant to use, with information in clear language and in the languages and formats in which the products and services are offered, including alternative formats, so that no complainant is disadvantaged. ^[2]
• Objectivity: handle every complaint in an equitable, objective and unbiased way. ^[2]
• Timeliness: handle complaints as quickly as feasible given their nature and the process used. ^[2]

In Gulf practice, the UAE Federal Tax Authority’s complaints policy states that it applies ISO 10002:2018, that no fees are charged for submitting, reviewing or processing a complaint, and that complaints are handled impartially with taxpayer data kept confidential. ^[5] Dubai’s General Directorate of Residency and Foreigners Affairs publishes how to complain, runs a multilingual system free of charge, and has staff sign confidentiality undertakings. ^[4]

The framework before the procedure

Before any form or IT system, the standard recommends in clause 5 a framework covering the context of the organisation, leadership commitment, a published policy and defined responsibilities and authority, followed in clause 6 by planning and design that set objectives, activities and resources. ^[2] In GDRFA Dubai’s approach this translates into measurable objectives, senior management oversight, and resources in the form of staff, training and systems. ^[4]

Where implementation most often fails is authority: a front-line employee receives the complaint but cannot approve compensation or an exception, and does not know who to escalate it to. The policy must therefore state who owns each decision and when a complaint is escalated.

The complaint journey from receipt to closure

The standard devotes clause 7 to operating the process. It has nine sub-clauses: it starts with communication about how to complain, followed by eight sequential steps from receipt to closure. ^[2]

GDRFA Dubai’s approach shows how these steps become a procedure: each complaint is logged with a serial number and its details and the customer is notified of receipt; it is then categorised, evaluated to confirm it is a genuine complaint, investigated, responsibility identified and action taken; the customer is told what was done and asked about their satisfaction; and the complaint is closed once the actions are confirmed as effective. ^[4]

The same approach classifies complaints into eight categories: service speed, access, front-line professionalism, ease of completing the transaction, quality of service information, privacy, environment, and administrative or financial errors. ^[4] A fixed classification is a precondition for later analysis: you cannot spot a trend in complaints logged under free-text headings.

Organisations need not build their forms from scratch. The standard’s informative annexes include a form for complainants (Annex C), a complaints-handling flowchart (E), a complaint follow-up form (F), an escalation flowchart (H) and guidance for small businesses (B). ^[2]

Clarification: what does the complainant actually want?

Many responses fail because they answer a question the complainant never asked. The UK Parliamentary and Health Service Ombudsman’s guidance, written to help organisations meet the NHS Complaint Standards, suggests clarification steps at the start of an investigation: acknowledge the complaint within three working days with a named contact, confirm the main issues with the complainant, understand the impact on them, identify the outcome they want while managing expectations, explain how evidence will be gathered and who will write the response, and agree a realistic timescale and how updates will be given. ^[3]

The three-day period is a UK standard for health service complaints; in your organisation the reference point is the service levels approved internally or by your regulator.

Preventing recurrence: from the case to the cause

Closing a complaint solves one customer’s problem; preventing it from recurring comes from clause 8: collecting information, analysing and evaluating complaints, evaluating complainants’ satisfaction with the process itself, monitoring, auditing, management review and continual improvement. ^[2] Among the standard’s stated aims is helping organisations identify trends and causes. ^[2]

In GDRFA Dubai’s approach, maintenance covers data collection, KPI monitoring, satisfaction surveys, internal audits, management reviews, and corrective and preventive actions. ^[4]

Hypothetical example: waiting-time complaints at a service centre

Hypothetical example: a service centre receives repeated complaints about long waits, and each one is closed with an apology.

1. Analysis: sorting service-speed complaints by day, hour and transaction type shows most relate to one transaction on Sunday mornings.
2. Cause: the transaction needs a document that is not mentioned in the service information, so customers have to come back twice.
3. Action: update the service information on the website and in text messages, and add a checklist at reception.
4. Verification: track the number of complaints in this category over the following months before closing the corrective action.

Note that the fix was not in the complaints team but in the service information. That is why analysis results must reach management review rather than staying in a monthly report.

Indicators that show whether the process is healthy

Clause 8 addresses monitoring the process and evaluating complainants’ satisfaction with it, but does not prescribe specific indicators. ^[2] Here is a practical starting set; set the targets according to your organisation’s approved service levels:

The fourth indicator matters most for prevention: if closure times fall while repeat complaints stay flat, the team has become faster at apologising, not the service better.

Conclusion

Managing customer complaints under ISO 10002 does not end with replying to the complainant. Build a framework with clear authority, run the steps from receipt to closure with a fixed classification, then analyse complaints regularly to reach their causes, and check that corrective action has actually reduced recurrence.