ISO 17025 Complaints Process: How to Handle and Resolve Complaints in Your Laboratory

Complaints are unavoidable in testing and calibration labs—but the way you handle them can either protect your accreditation or create audit findings. A well-designed ISO 17025 complaint process (ISO/IEC 17025:2017 Clause 7.9) should be documented, impartial, and fully traceable so you can prove you took the issue seriously, investigated using evidence, and communicated outcomes appropriately while protecting confidentiality.

I’m Ralph Martin (RJ Quality Consulting), a certified ISO/IEC 17025 assessor and quality consultant. In this guide, I’ll walk you through a practical complaints process you can implement in a real lab—without overcomplicating it—based on what accreditation bodies typically look for when they review complaint logs, investigation records, decisions, and follow-up actions during assessments.

By the end of this article, you’ll know exactly how to:

• Receive and log complaints (including informal ones) in a way that stands up to an audit
• Screen and assign complaints to maintain impartiality and avoid conflicts of interest
• Investigate using objective evidence (records, methods, equipment history, staff input)
• Decide and document outcomes, including when a complaint becomes nonconforming work or triggers corrective action
• Communicate results to the complainant clearly and professionally, with the right level of detail
• Retain the right records so you can show compliance quickly during an assessment
  

Key Takeaways

• ISO/IEC 17025:2017 Clause 7.9 requires a defined, impartial, and traceable complaints process—from receipt and evaluation through investigation, decision, and communication—supported by retained records.
• Complaints are a built-in improvement signal, feeding corrective action, risk-based thinking, and management review so the system gets stronger over time.
• Strong complaint handling protects your lab’s credibility and technical validity by safeguarding impartiality, controlling communications and confidentiality, and ensuring results and reporting decisions are evidence-based.

Video Walkthrough: ISO 17025 Complaints Process (Clause 7.9)

Want the quick, practical version before you read the full guide? In the video below, I walk you through a simple, audit-ready ISO 17025 complaints process aligned to ISO/IEC 17025:2017 Clause 7.9—from receiving and validating complaints to assigning an impartial reviewer, investigating with evidence, communicating outcomes, and keeping the records an assessor will expect to see. If you prefer learning by example, watch the walkthrough first, then scroll down for the step-by-step breakdown and templates you can model in your lab.

Why the ISO 17025 Complaints Process Matters

Accreditation bodies actually see complaints as a valuable source of information, not just problems to hide. ANAB explains this in their article on how laboratories can benefit from complaints, highlighting that a structured complaints process required by ISO/IEC 17025 can drive meaningful improvement.

The ISO/IEC 17025 complaints process gives you a practical way to address problems that pop up in your work. You get a routine: receive, review, and resolve complaints the same way, every time. This keeps decisions fair and confusion at bay.

When you respond to concerns promptly and with real answers, you protect customer satisfaction. People don’t want to be ignored or kept waiting. A defined process helps you deliver what they expect.

The standard also guards impartiality. You hand off complaints to someone who wasn’t involved. That builds trust and keeps things objective.

Every complaint can highlight a risk or a weak spot. If you pay attention, you’ll fix the root causes and avoid repeat headaches.

Why does this process matter?

• Compliance: ISO/IEC 17025 says you need a documented, working process.
• Consistency: You treat similar issues the same way, every time.
• Traceability: You keep records showing what you did and why.
• Improvement: You use complaints to make your procedures better.

Auditors want to see proof you’re handling complaints. A working process shows you’re in control and care about your customers.

What ISO 17025 Requires for Complaints (Clause 7.9 in Plain English)

ISO/IEC 17025 Clause 7.9 spells out how you handle complaints in testing and calibration labs. You need a clear, working process that treats complaints fairly.

Make it easy to receive complaints. Clients might call, email, or use another method. Log every complaint—even the informal ones.

Next, review and validate the complaint. Does it involve your lab’s activities or quality system? If yes, keep going. Don’t brush it aside.

Assign the complaint to someone independent—not involved in the work in question. Independence keeps things fair.

Then, investigate and act. Dig into records, talk to staff if needed, and get the facts. Take whatever action fixes the problem and stops it from happening again.

Communicate with the complainant. Confirm you got their complaint, update them as needed, and explain the final decision. Keep it respectful and straightforward.

Keep documented records. Log all the details: the complaint, your investigation, actions, and your response.

Clause 7.9 key requirements at a glance:

Requirement	What you must do
Receipt	Accept and log complaints
Review	Confirm validity and scope
Independence	Assign to someone without a conflict of interest
Investigation	Check facts and causes
Communication	Keep the complainant informed
Records	Keep full documentation

Designing a Practical ISO 17025 Complaints Process

A good complaints process moves step-by-step, from intake to closure. Each step should protect impartiality, dig into root causes, and leave a record you can stand behind in an audit.

Step 1 – Make the Complaints Process Visible and Accessible

People need to know how to complain. ISO 17025 expects you to keep the door open—no hoops to jump through.

Share the process on your website, in contracts, or in your quality manual. Give clear contact info: an email or phone number works.

Skip the legalese. Use everyday language.

Say what info you need but don’t force people to use a fancy form. Take complaints however they come—in writing, by phone, whatever works.

Train your staff so they know how to forward complaints. One missed message can mess up your tracking and slow everything down.

Step 2 – Receiving and Logging Complaints

Log every complaint as soon as you get it. Don’t wait to decide if it’s “real.”

Capture the basics in a record:

• Date received
• Complainant’s name and contact
• Description of the issue
• Service or report involved

Any system works—spreadsheet, database, QMS software—as long as it’s complete and up to date.

Send a quick acknowledgment, ideally within a day or two. It shows you’re on it and keeps people from chasing you.

Step 3 – Screening and Classifying Complaints

Check if the complaint falls under your lab’s scope. This keeps you focused and avoids wasting time.

Does it relate to testing, calibration, reporting, or staff? If not, note the reason and close it out.

Sort valid complaints by type. You’ll see patterns over time—technical issues, delays, communication, or staff behavior.

Hand the case to someone independent. That’s key for credibility and fair decisions.

Step 4 – Investigating the Complaint

Focus on facts, not blame. Gather evidence to figure out what really happened.

Check test records, procedures, and equipment logs. Talk to staff only if you need more info and jot down what they say.

For bigger issues, use simple root cause tools like:

• 5 Whys
• Cause-and-effect review
• Timeline analysis

Don’t guess. Let records and data guide you.

Document each step. Auditors want to see your reasoning—not just hear it.

Step 5 – Deciding on Actions and Corrective Actions

Decide what’ll resolve the complaint and stop it from happening again. Not every issue needs full corrective action, but every outcome needs a reason.

Common actions:

• Fix a report
• Repeat work
• Clarify results to the customer
• Update procedures or staff training

If you find a system problem, raise a corrective action and link it to the complaint.

Assign someone to own the fix and set deadlines. Track it until it’s done.

Check if your solution works—especially if it’s a recurring problem.

Step 6 – Communicating the Outcome to the Complainant

Let the complainant know what happened. Do it in writing.

Explain what you found and what you did, using plain language. Skip the jargon.

If you reject the complaint, back it up with facts.

Don’t drag your feet. Delays erode trust and raise questions during audits.

Keep it respectful and neutral. Only admit fault if you have evidence.

Note how and when you communicated in your records.

Step 7 – Closing and Reviewing the Complaint

Close the complaint only after all actions are done. Open issues are just that—open.

Confirm that any corrective actions are finished and worked. Update your log with closure info.

During audits or management review, look at closed complaints for trends—repeat causes, process holes, or training needs.

Keep your records according to your retention policy and make sure you can find them fast if someone asks.

What Your ISO 17025 Complaints Procedure Should Include

Your complaints procedure needs to lay out clear steps, say who’s responsible for each part, and link outcomes back to your quality management system. It also needs to show how you document decisions, protect impartiality, and communicate results to the person who complained.

Key Elements of a Written Complaints Procedure

Your written procedure should explain how you receive, review, investigate, and resolve complaints about lab activities. Keep it straightforward—no need for a maze.

At a minimum, include:

• How to take in complaints (email, phone, forms, etc.)
• What counts as a formal complaint
• Rules for impartial review (no self-investigation)
• Who handles what—review, investigation, approval
• What records to keep and for how long

Show how complaints feed into corrective actions and system improvements. If you change something because of a complaint, record it.

If you use quality management software, mention how it logs, tracks, and stores complaints. That’ll help during audits.

Example Complaints Workflow

A simple, repeatable workflow keeps everyone on the same page and shows auditors your process actually works.

One ISO 17025–friendly workflow might look like:

Step	Action
Receipt	Log the complaint with date, source, and issue
Validation	Check if it’s about your accredited work
Assignment	Hand it to an independent, qualified person
Investigation	Review records, staff input, and procedures
Decision	Decide if it’s valid and what needs to be done
Response	Tell the complainant the outcome
Records	Store results and link to corrective actions

Acknowledge complaints quickly and keep people in the loop if things take time. Document each step so your quality system shows real control and accountability.

Complaints, Nonconforming Work, and Corrective Action – How They Fit Together

Complaints often point to deeper problems in how you run things. ISO 17025 wants you to connect complaints, nonconforming work, and corrective action so you actually improve, not just patch things up.

When a complaint reveals incorrect results, sample mix-ups or other serious issues, it isn’t just a customer-service problem—it’s nonconforming work. For a deeper look at how to manage those situations, see my article on ISO 17025 nonconforming work
.

When a Complaint Indicates Nonconforming Work

If a complaint shows your lab missed a requirement—whether it’s from ISO 17025, your own rules, or what you promised the customer—that’s nonconforming work.

It’s worth pausing to ask:

• Did the result, report, or service break a rule?
• Did staff follow the right methods and instructions?
• Did this issue put result validity or customer trust at risk?

If you answer yes, you need to treat it as nonconforming work. This means more than just telling the customer you’re sorry. You might have to stop work, check old results, or let other clients know.

Make sure you record how the complaint links to the nonconforming work. Auditors want to see this documented.

Feeding Complaints into Corrective Action

If a complaint shows your system failed, you’ve got to kick off corrective action. Just reissuing a report won’t cut it if the problem could pop up again.

Corrective action digs for root cause. Why did this happen, and how did it slip through? That’s the mindset you need—even if your system calls it something else.

Steps usually include:

• Find the real cause, not just the symptom
• List out actions to keep it from happening again
• Make it clear who’s doing what and by when
• Check that your fixes actually work

Document how the complaint led to corrective action. This kind of traceability is what auditors look for.

Serious or repeated complaints should feed directly into your corrective action system, not just be “patched up” and forgotten. If you want help structuring that part, my article on Corrective Action in ISO 17025 walks through how to identify root causes, implement durable fixes, and verify they’re actually working.

Complaints, Impartiality and Confidentiality

ISO 17025 wants you to handle complaints fairly and securely. Keep decision-makers separate from the original work and protect sensitive info the whole way through.

Avoiding Conflicts of Interest in Complaint Handling

Assign complaints to staff who weren’t involved in the work. Otherwise, even a fair decision can look biased. It’s just safer for your reputation.

Spell out this rule in your procedure—who assigns, who investigates, and when things get escalated. In small labs, this might mean pulling in a quality manager, a senior manager, or even someone from outside.

Some controls that help:

• Independence: Don’t let people review their own work
• Authority: Give investigators the power to act
• Documentation: Always record what you decided and why

These steps help show compliance and build trust in your outcomes.

Protecting Confidential Information

Keep all complaint-related info locked down—client data, test results, staff names, internal records, the lot. ISO 17025 expects you to tightly control access and avoid leaks at every stage.

Limit complaint details to staff who need them to investigate. Don’t share names or findings outside this group unless required by law or your accreditor. Store records securely, digital or paper—it doesn’t matter, just keep them safe.

Good habits include:

• Restricting access to complaint files
• Clear rules for sharing info with clients
• Secure retention that matches your record policy

When you share results, only give what’s needed. It protects everyone—clients, staff, and the lab itself.

Using Complaints for Risk Management and Continual Improvement

Complaints show you exactly where your system cracks. Use them to spot risks early and keep improving your ISO 17025 setup.

Complaints as a Source of Risk Information

Each complaint flags a real risk—maybe it’s staff, a method, equipment, or just a communication gap. Don’t treat it as just a customer problem; feed it into your risk process.

When you look at a complaint, ask:

• What failed, and where?
• What’s the risk if it happens again?
• Who or what gets affected?

Connect the outcome to preventive action. If you spot a risk before it bites, change the process, train someone, or update controls. That’s how you close the loop between complaints and risk management.

Record how complaints feed into your risk review. Auditors will check for this.

Trending and Reviewing Complaints

One complaint matters, but patterns matter more. Review complaint data regularly—maybe during management review.

Track these details in a way that works for you:

• Type of issue
• Process or area
• Root cause
• Action taken

Even a simple table or log can help you spot repeat issues. Patterns usually mean there’s a bigger system problem, not just a fluke.

Trending helps you figure out where to focus. When you act on trends, you make your system stronger and cut down on future complaints.

Keep the loop going. Review what changed, see if complaints drop, and adjust as needed.

Common Nonconformities with ISO 17025 Complaints Processes

Labs often get dinged for not having a documented complaints process. ISO 17025 wants a clear method for handling complaints—verbal “fixes” don’t count.

Another issue: not recording complaints. Some labs just fix problems quietly and move on, but auditors want written proof of what happened and how you handled it.

Impartiality trips up a lot of labs. If the person who did the work also investigates, you’re asking for trouble. Assign complaints to someone not involved.

Poor communication also causes findings. Always acknowledge complaints and tell the customer the outcome. Silence or slow replies often lead to audit trouble.

If you don’t define what counts as a complaint, staff will handle things differently. That inconsistency weakens your system.

Problem areas pop up like:

• Missing or incomplete complaint records
• No set response timelines
• Unclear roles and responsibilities
• Complaints not tied to corrective actions

Sometimes complaints get closed without a real investigation. Auditors expect proof that you looked into it and did something about it. Skipping this step makes your quality system look shaky.

If complaints keep coming up and you don’t take preventive action, expect a major nonconformity. ISO 17025 wants you to use complaints to improve, not just put out fires one by one.

Practical Tips for Small and Busy Laboratories

Small labs are usually pressed for time and people. But you can still meet ISO 17025 by keeping things clear and making sure everyone handles complaints consistently and fairly.

Keep the ISO 17025 Complaints Process Simple

Reduce risk by using a short, clear process. One simple procedure should cover receiving, reviewing, investigating, deciding, and responding.

Use a single form or log for every complaint. Note the date, issue, who handled it, and the final decision. Auditors look for this record.

Don’t overcomplicate it. Assign one person—maybe the quality manager or lab lead—to run the process. If that person worked on the case, hand it to someone else qualified.

No need for fancy tools. A spreadsheet or shared folder is fine as long as it stays organized and controlled.

Stick to what ISO requires:

• Clients can submit complaints
• Someone independent reviews the issue
• Clear communication of the outcome
• Records kept for the right amount of time

Training Staff to Respond Calmly and Consistently

Protect your lab by making sure staff know how to handle complaints right. Train them to listen, stay calm, and avoid blame games.

Give them a short script for first contact—something like: “We take your concern seriously and will review it under our complaints process.” It keeps things consistent.

Teach staff to pass complaints up the chain, not fix them on the spot. That supports impartial reviews and cuts down on mistakes.

Do a short training every year. Use real examples, but don’t name names.

Main points to cover:

• What counts as a complaint
• Who logs it
• What staff should and shouldn’t say
• When to escalate

Clear training lowers stress and helps everyone handle complaints the same way.

Tools, Templates, and Next Steps

Good tools and clear next steps make complaint handling easier and more consistent. Templates, routine checks, and the right support help you avoid mistakes and save time.

Templates to Save Time

Templates make sure you capture the right info every time. They also make audits smoother.

Try a basic complaint log for:

• Date received and source
• Description of the issue
• Person assigned and independence check
• Status and close date

A complaint investigation form should cover facts, findings, and actions. Keep it simple and clear.

Use a response template for client replies. It keeps your messages consistent and professional.

Template	Purpose
Complaint Log	Track and monitor all complaints
Investigation Form	Document review and decisions
Response Letter	Confirm outcome to the client

Store templates in a controlled spot and review them regularly.

Internal Audits and Management Review of Complaints

Complaints feed directly into your internal audits. Auditors should check that you follow your process and keep complete records.

During an audit, check:

• Complaints are logged and investigated
• Independent staff make the decisions
• Records show what happened and what you did

Management review should look for patterns, not just one-off events. Watch for repeat issues, slow responses, and links to nonconforming work.

Include complaint data in management review at least once a year. Write down what you decide and any changes you need to make.

Review your process from time to time to make sure it still fits your lab’s size and risk level.

Get Help If You’re Unsure

If you’re not sure what to do, get help early. Little gaps can turn into audit findings if you ignore them.

Ask:

• Your quality or technical manager
• An external consultant with ISO 17025 experience
• Your accreditation body, if you need clarification

Get help for specific issues, like independence or record details. Don’t just copy generic procedures—they rarely fit your lab.

Write down any guidance you use and review it at your next management review. This shows you’re in control, even if you tweak your approach.

Frequently Asked Questions

This section covers how ISO 17025 expects you to handle complaints—from receiving to resolving them. It also explains roles, records, and controls that keep things fair, traceable, and trustworthy.

What steps should be followed when handling a complaint in a laboratory accredited under ISO 17025?

Log the complaint right away, no matter if it comes in by phone, email, or even just a casual chat. Make sure it actually concerns your lab’s activities and fits within your scope.

Hand off the complaint to someone who wasn’t involved in the original work. They’ll dig into the issue, decide what to do, and jot down what they find.

Let the complainant know what happened and what you’ve done, and try to do it promptly. Keep records of every step for later review or audits.

How does the ISO 17025 standard define a complaint?

ISO 17025 calls a complaint any expression of dissatisfaction—basically, if someone’s unhappy about something related to your lab’s work or results and wants a response.

It doesn’t have to be formal or even written. If a client expects an answer or some action, treat it as a complaint.

What documentation is required for the complaint process in an ISO 17025 accredited laboratory?

Keep records that show what happened and what actions you took. These help with traceability and accountability.

Usually, you’ll need to note the complaint details, dates, and how it came in. Record who handled it, what you found, and what you did about it.

Hold onto the final decision and any messages you sent back to the complainant. Follow your own policy for how long you keep these records.

What are the responsibilities of laboratory personnel during the complaint handling process?

Treat every complaint as important and put it into the proper process. Don’t ignore issues just because they seem minor or are phrased casually.

If you’re the one investigating, stick to the approved steps and record what you actually find—don’t just guess. Focus on facts and evidence.

Support corrective actions if they’re needed, and take part in reviews or audits about complaint patterns.

How should a laboratory ensure impartiality and confidentiality during the complaint resolution process?

Give complaints to staff who weren’t involved in the original work. This helps keep things fair and credible.

Only let authorized people see complaint records, and share info strictly on a need-to-know basis.

Protect the identities of both the complainant and staff whenever you can. Stick to your confidentiality policy throughout.

What is the role of top management in the ISO 17025 complaint handling process?

Top management signs off on the complaints procedure and makes sure there’s enough staff, time, and authority to handle things.

They review complaint data during management reviews and look for trends to improve processes and avoid repeated problems.

It’s on them to keep the process fair and effective, and to make sure actions fit with your quality management system.

Conclusion

When you treat complaints as controlled inputs, not just annoyances, your ISO 17025 system gets stronger. Having a clear process lets you act quickly, handle things fairly, and keep records that actually hold up if anyone checks.

Clause 7.9 expects you to receive, review, investigate, and close complaints independently. You keep the complainant in the loop and write down what you did at each step. That way, you protect impartiality and make sure things are traceable.

A solid complaints process should:

• Give access to anyone with a stake
• Assign independence from the work being questioned
• Document evidence and decisions as you go
• Communicate outcomes without dragging your feet

It’s smart to connect complaints with audits and management review. You’ll start to see patterns—risks, training gaps, or broken processes. That’s how you figure out what needs fixing and actually track if things get better.

You don’t need fancy tools. A simple log, clear roles, and sticking to a set timeline keep things on track. Pick a record retention period and actually follow it—consistency matters.

When you stick to these habits, you show you’re in control, you’re transparent, and you actually care about feedback. Plus, you keep your management system in line with ISO 17025. Not bad, right?