Supplier audit: what to look at when you only have one day

A supplier audit is a day, sometimes two, spent deciding whether a company you depend on does what its documents say it does. It is not an inspection of everything and it cannot be. You will see perhaps two per cent of what happens there, chosen by you, in a week they knew you were coming — which means the whole value of the exercise sits in what you choose to sample and how hard you pull on the threads that look loose.

Preparing a supplier audit that is worth the trip

• Decide the scope in writing beforehand: which product, which processes, which standard or contract clauses you are auditing against.
• Read what you already have — their previous findings, your own goods-in rejection history, their complaint responses. Half the useful questions come from your own data before you arrive.
• Pick two or three threads to trace end to end rather than sampling twenty things shallowly. One order followed from purchase order through production records to dispatch tells you more than a tour.
• Send the agenda, and ask for the documents you want available. What arrives late or not at all is itself information.
• Agree who from their side needs to be present, including someone who can commit to actions.

What to actually look at

1. Trace one batch backwards from a delivery you received: the batch record, the raw material lots, the release decision, the certificate of analysis that went with it.
2. Check that the process the operator describes matches the procedure on the wall and the record in the file. Where these three diverge, the record is usually the fiction.
3. Look at how a problem was handled, not whether problems exist. Ask for their last three non conformance reports and follow what happened to each.
4. Check calibration and maintenance evidence for the equipment that determines your product’s conformity, not for the whole plant.
5. Ask what changed since your last audit — process, ownership, key staff, subcontractors — because unnotified change is the most common cause of a surprise defect.

A supplier who cannot show you a record is not necessarily failing; a supplier who produces a perfect record for something that clearly does not happen is a much more serious finding. Documented fiction is worse than an honest gap, because it means the rest of the file cannot be relied on either.

Findings, and what they are worth

• Grade findings consistently — critical, major, minor — and define the grades in advance rather than in the moment.
• State the objective evidence for each: what you saw, which record, which date. A finding without evidence is an opinion and will be argued away.
• Reference the requirement it breaches. "Poor housekeeping" is not auditable; a clause and an observation is.
• Ask for root cause, not just a fix. A corrective action that addresses the instance and not the cause guarantees the same finding next year.
• Set closure dates and actually verify them. An audit whose findings are never verified closed teaches the supplier that the audit is theatre.

Where the audit lives

Ettex Forms gives the audit a consistent shape — the same checklist, the same grading, the same fields for evidence — so that two auditors produce comparable reports and a supplier can be tracked across years rather than assessed afresh each visit. Findings become dated records with owners and due dates, which is what makes closure verifiable instead of remembered. It sits alongside the supplier onboarding file, where the qualification decision was made in the first place. Ettex does not certify suppliers, does not provide audit standards and cannot tell you whether a finding is major — the judgement is the auditor’s.