What should a root cause analysis report include?

The problem stated as a fact, the containment, the evidence and a timeline, the analysis, the verified root causes and the causes ruled out, corrective and preventive actions with owners and dates, an effectiveness check against a target, and sign-off.

When should I use this report instead of a 5 Whys, a fishbone, an A3 or an 8D?

The 5 Whys template and the fishbone board are tools that go inside it: the 5 Whys follows one chain of cause and effect, the fishbone lays out possible causes by category. Use an A3 when you need to agree a plan with managers on one sheet, from background to follow-up. Use the 8D report for customer complaints and other problems that need a formal team response with occurrence and escape causes. Use the incident investigation report for injuries and other safety incidents. This report is the general record for everything else.

What is the difference between a corrective and a preventive action?

In this template a corrective action removes the verified cause where the problem happened. A preventive action stops the same cause elsewhere: on similar machines, parts or lines, or in the system, such as the PFMEA, the control plan or a procedure.

How do you verify a root cause?

Show that the cause explains the facts and that removing it removes the problem: switch the cause on and off and watch the defect follow, compare data from before and after, or check it at the gemba. A cause agreed in a meeting but never tested is still a hypothesis.

When can a root cause analysis be closed?

When every action is done and the effectiveness check shows the measure met its target over a period long enough to trust, often several weeks or production runs. The Excel version flags late actions and shows when the report is ready to close.

Free template

Updated September 30, 2026

Root cause analysis template

A root cause analysis (RCA) report records how a problem was investigated and fixed: the problem stated as a fact, the containment that protects the customer, the evidence, the analysis, the causes that were verified and the ones ruled out, the corrective and preventive actions, and the check that proves the problem stayed away. It works with any method: the analysis box holds a 5 Whys chain and a 6M fishbone summary, and the report is the record around them. Page 1 of the PDF covers the problem statement, containment, the data reviewed with a timeline, and the analysis. Page 2 has the verified root causes with how each was verified, the causes ruled out, the actions with owners and dates, the effectiveness check against a baseline and a target, where the fix was standardized, and sign-off. The Excel version tracks the second half: each action gets a status that flags late and done-late actions, each effectiveness measure is checked against its target, and it shows whether the RCA is ready to close.

Free to use: print it, copy it and edit it for your team. Enter your name and work email once to download.

Page 1 of the root cause analysis template: fields for RCA number, owner and team, a problem statement table, a containment table, a timeline with the data reviewed, and an analysis box with a 5 Whys chain and a six-category fishbone summary. — Problem statementContainmentData and timeline5 Whys and fishbone summaryVerified and ruled-out causesCorrective and preventive actionsEffectiveness checkSign-off

When to use it

When to use a root cause analysis report

A problem worth more than a quick fix but not one that needs a formal 8D for a customer: a repeat defect, a chronic stoppage, an internal audit finding.
When the fix has to be proved: the report stays open until the effectiveness check shows the problem stayed away.
When you need one record that holds the evidence, the analysis, the actions and the sign-off, whatever tool found the cause.
As the written follow-up to a 5 Whys or fishbone session, so the actions and the proof are not lost.

How to fill it in

1
State the problem as a fact
What is wrong, where, since when, how big and against what standard. No cause and no fix in the statement.
2
Contain it
Protect the customer first: sort, quarantine, add a check. Note whether the containment worked.
3
Collect the evidence
Records, process data, maintenance history, photos and the people involved. Put what happened in time order.
4
Analyze
Follow the main chain with the 5 Whys and use the fishbone summary to make sure no category was skipped. Mark each answer you checked.
5
Verify the root causes
Keep a cause only when data or a test confirms it, and write down what you ruled out and why.
6
Act and prove it
Corrective actions for each verified cause and preventive actions for similar lines or the system, each with an owner and a date. Close only when the effectiveness check meets the target.

A filled-in example

Illustrative, not a benchmark

An example: torque failures at the end-of-line test on a gearbox assembly line (illustrative).

Problem: 46 of 3,200 gearboxes (1.4%) failed the torque test in two weeks, against a usual 0.2%, all from line 2.
Containment: a 100% torque check on line 2 and a sort of 1,100 units in the warehouse, which found and held 9 more.
Analysis: the 5 Whys traced the low torque to a nutrunner whose calibration had lapsed. The fishbone check of material and method found nothing else.
Verified: the nutrunner read 8% high against a torque analyzer. A new fastener lot was suspected and ruled out by testing 30 parts from it.
Actions: recalibrate the tool and add it to the calibration schedule (corrective); check every nutrunner in the plant against the schedule (preventive).

The effectiveness check tracked the failure rate for four weeks: 3 failures in 6,400 units, about 0.05%, below the 0.2% target, so the report was signed off and the lapsed-calibration check was added to the monthly audit.

Common mistakes

A problem statement that names the cause
'Failures due to a bad tool' closes the investigation before it starts. Describe what is wrong, not why.
Skipping containment
The analysis can take days. The customer needs protecting today.
Taking the first likely cause as the root cause
Verify it with data or a test, and record what you ruled out, so the next person does not chase it again.
Only corrective actions
Fixing the one machine leaves the same cause on the others. Add preventive actions for similar lines, parts and the system.
Closing on the action date
An action done is not a problem solved. Close when the effectiveness check shows the result held.

Download the template

Free to use: print it, copy it and edit it for your team. Enter your name and work email once to download.

Run this template in LeanSuite

In LeanSuite the RCA Agent in every Kaizen and EWO drafts a 5 Whys, 4M1D and fishbone from the problem, your attached manuals and SOPs and your plant's past problems, you edit the draft, and the countermeasures you keep go into the action plan with an owner and a due date.

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