What calibration records should I give a customer?

The records for the instruments used on their product. That is a list with each instrument's ID, calibration date, due date and status, plus the latest certificate or internal calibration record for each, with the as-found and as-left results. Add the accreditation evidence for outside labs and the reference standard certificates for in-house work when they ask, and any out-of-tolerance assessment from the period.

Does a calibration certificate have to come from an ISO/IEC 17025 accredited lab?

Not under ISO 9001, which asks for traceable calibration but not accreditation. IATF 16949 clause 7.1.5.3.2, as revised by sanctioned interpretation 10, expects an external lab accredited to ISO/IEC 17025 or a national equivalent by a signatory of the ILAC MRA, with the calibration in its scope and the accreditation mark on the certificate. When a lab without that accreditation is used, you need evidence that it was evaluated and meets the internal laboratory requirements of clause 7.1.5.3.1. Any customer can also require accredited calibration in its own terms.

What does a supplier quality engineer check on a calibration certificate?

That it names the right instrument, that the calibration came before their parts were measured and was not overdue, and that the as-found results were within tolerance or have an assessment. They also look for the uncertainty with its coverage factor, a traceability statement with the reference standards, the decision rule behind any pass or fail, and a named approver. Where accreditation is required, they check the mark and the lab's scope.

What if a gage used on the customer's parts was out of tolerance?

Send the record anyway, with your assessment of the product it measured and the action you took. ISO 9001 clause 7.1.5.2 asks you to determine whether earlier results were adversely affected and to act. If suspect product may have reached the customer, tell them directly before they find it in the records, and follow the notification terms in your quality agreement.

Is a NIST traceable certificate enough for my customer?

Only if their requirements stop at traceability. NIST's policy says the provider of a result has to support its own traceability claim, and NIST does not certify the claims of other organizations. A customer that requires accredited calibration looks for the accreditation mark and a scope that covers the calibration, not just the words NIST traceable.

Do I have to send my whole calibration register?

Not unless your agreement says so. Send the records for the instruments and the period they asked about. A register extract that lists each instrument with its certificate number, calibration date and due date lets them choose which certificates to review.

Compliance and audits

Customer requests for calibration records: what to send and what they check

9 min read Published November 7, 2026

When a customer asks for calibration records, send the certificates or internal calibration records for the instruments used on their product, with the as-found and as-left results, the due dates and the evidence of traceability. If their requirements call for an accredited lab, add proof that the lab's accreditation covers each calibration.

On this page

Why a customer asks for calibration records

A customer may ask during a supplier audit, while approving a new part, or after a complaint or a part that measured differently at their end. Each time they want the same evidence. The instruments that accepted their product were calibrated, traceable and within tolerance when they were used.

Their right to see the records is usually set out in your purchase order, a quality agreement or their supplier quality manual. Read it before you reply. It may say which records they can see, in what form and how fast. AS9100 has organizations pass a right of access to records down their supply chain, so an aerospace purchase order can carry one.

What to send

Send the records for the instruments and the period they asked about. A complete answer usually has these parts.

A list of the instruments used on their parts, with each one's ID, description, last calibration date, due date and status. An extract from your register does this.
The latest certificate for each instrument calibrated by an outside lab, and your own calibration record for each one calibrated in-house.
Earlier certificates as well when they ask about a period, such as the months their parts were made.
The as-found and as-left results. If a certificate reports only the final readings, say so.
For outside labs, the lab's accreditation certificate and the part of its scope that covers the calibration, when their requirements call for accredited calibration.
For in-house calibrations, the certificate of the reference standard you used, and the procedure if they ask for it.
For any instrument found out of tolerance in that period, your assessment of the product it measured and the action you took.

As-found and as-left readings

Tip: Send what was asked for and no more. Your full register and other customers' records are not part of the answer.

What they check on each certificate

A certificate from a lab that works to ISO/IEC 17025 carries more than an ordinary report. Clause 7.8.4 adds the measurement uncertainty, the conditions that influenced the results, a statement of how the results are metrologically traceable, the results before and after any adjustment or repair where they are available, and any statement of conformity.

A supplier quality engineer reads each certificate for a handful of points. Check them yourself before you send it.

Identity. The serial number or ID on the certificate matches the instrument and your list.
Dates. The instrument was calibrated before their parts were measured, and it was not past its due date when it measured them.
As-found results. They were within tolerance, or there is an assessment of the product measured while they were not.
Uncertainty. It is stated with its coverage factor and is small enough for the tolerance the instrument checks.
Traceability. The certificate states how the results are traceable and identifies the reference standards used.
Conformity. A pass or fail statement names the decision rule behind it, unless the specification or standard already sets the rule.
Approval. A named person authorized the certificate.

Calibration certificate requirements

Tip: ISO/IEC 17025 clause 7.8.4.3 does not allow a calibration interval recommendation on a certificate or label unless it was agreed with the customer. Your due date comes from your own interval, not from the lab.

When the outside lab has to be accredited

ISO 9001 does not require an accredited lab. Where measurement traceability is a requirement or is essential to confidence in the results, ISO 9001 clause 7.1.5.2 requires calibration or verification against measurement standards traceable to international or national measurement standards. Your customer's own requirements can go further, and automotive requirements do.

Under IATF 16949 clause 7.1.5.3.2, as revised by sanctioned interpretation 10, an external lab needs a defined scope that covers the calibration you buy, and one of two things. Either it is accredited to ISO/IEC 17025 or a national equivalent by a signatory of the ILAC MRA, with the calibration in its scope of accreditation and the accreditation body's mark on the certificate. Or, where a lab without that accreditation is used, for example for specialist equipment or by the equipment maker, there is evidence that it was evaluated and meets the internal laboratory requirements of clause 7.1.5.3.1. IATF FAQ 14 confirms that an accredited lab's certificate has to carry the mark.

A customer that checks accreditation looks at these points.

The accreditation body is a signatory of the ILAC MRA, or of a regional arrangement that ILAC recognizes.
The lab's scope of accreditation covers the quantity and the range of the calibration.
The certificate carries the accreditation mark or a reference to the lab's accreditation. ILAC-P10 says only such certificates fully benefit from the recognition the arrangement brings.
The reported uncertainty is not smaller than the calibration and measurement capability (CMC) in the lab's scope. ILAC-P14 does not allow an accredited lab to report less.

Tip: A certificate that says NIST traceable carries a claim by the lab, not an approval from NIST. NIST's traceability policy says the provider of a result has to support its own claim, and NIST does not certify the claims of other organizations.

Close the gaps before you reply

Pulling the records together can turn up problems. Deal with them before you send anything, so the customer hears about them from you.

An instrument past its due date. Take it out of use, calibrate it and check whether it measured their parts while it was overdue.
A missing certificate. Ask the lab that did the work for a copy.
A serial number on the certificate that does not match the instrument. Ask the lab whether it made a typing error or calibrated a different instrument. A typing error needs an amended or reissued certificate. If it was a different instrument, treat yours as not calibrated.
An out-of-tolerance result with no assessment. ISO 9001 clause 7.1.5.2 asks you to determine whether earlier results were adversely affected and to take appropriate action. Do that now and include it.
An outside lab that is not on your approved supplier list, or whose accreditation does not cover the calibration.

Tip: If suspect product may have reached the customer, tell them directly and follow the notification terms in your quality agreement. Do not leave them to find it in the records.

How to answer a request, step by step

Confirm what they want: which parts or instruments, which period, what format and by when.
List the instruments used on those parts, from the control plan, the inspection plan or the inspection records.
Pull the register entries for those instruments: ID, calibration date, due date and status.
Collect the certificate or internal record for each one, and earlier ones if they asked about a period.
Check each record for identity, dates, as-found results, uncertainty, traceability and approval.
Add the accreditation evidence for outside labs where it is required, and the reference standard certificates for in-house work.
Close the gaps. Get missing certificates from the lab and include the assessment for any out-of-tolerance result.
Send one indexed file, and keep a note of what you sent, to whom and when.

Keep the records ready for the next request

The quickest answer is one you prepared earlier. Review each certificate when it arrives, not when a customer asks. Keep it with the instrument's record, enter the as-found and as-left results as data, and keep each outside lab's scope of accreditation with its entry on your approved supplier list.

Keep the history as well as the latest certificate. ILAC-G24 / OIML D 10 recommends keeping calibration results as history for later interval decisions, and the same history answers a question about a past period.

Taking over a calibration program

How Axiospec handles a customer records request

Axiospec is calibration management software. Each instrument keeps its calibration history with the as-found and as-left readings, the reference standard used, the service provider and the files attached to each calibration, such as the lab's certificate.

To answer a request, export an audit pack scoped to one instrument, a site or a location, and to a date range. The ZIP holds a summary PDF, CSV files of the calibration records and measurement points, the latest certificate Axiospec generated for each instrument and the main file attached to each calibration. You can also invite an auditor as a read-only user with an end date. Axiospec does not make a lab accredited or decide whether your records meet a customer's terms. Those judgments stay with you and your customer.

It is free for up to 50 active instruments. A new workspace runs Professional for 45 days with room for 1,500, and we load your existing records for you at no cost on every plan.

Common questions

What calibration records should I give a customer?: The records for the instruments used on their product. That is a list with each instrument's ID, calibration date, due date and status, plus the latest certificate or internal calibration record for each, with the as-found and as-left results. Add the accreditation evidence for outside labs and the reference standard certificates for in-house work when they ask, and any out-of-tolerance assessment from the period.
Does a calibration certificate have to come from an ISO/IEC 17025 accredited lab?: Not under ISO 9001, which asks for traceable calibration but not accreditation. IATF 16949 clause 7.1.5.3.2, as revised by sanctioned interpretation 10, expects an external lab accredited to ISO/IEC 17025 or a national equivalent by a signatory of the ILAC MRA, with the calibration in its scope and the accreditation mark on the certificate. When a lab without that accreditation is used, you need evidence that it was evaluated and meets the internal laboratory requirements of clause 7.1.5.3.1. Any customer can also require accredited calibration in its own terms.
What does a supplier quality engineer check on a calibration certificate?: That it names the right instrument, that the calibration came before their parts were measured and was not overdue, and that the as-found results were within tolerance or have an assessment. They also look for the uncertainty with its coverage factor, a traceability statement with the reference standards, the decision rule behind any pass or fail, and a named approver. Where accreditation is required, they check the mark and the lab's scope.
What if a gage used on the customer's parts was out of tolerance?: Send the record anyway, with your assessment of the product it measured and the action you took. ISO 9001 clause 7.1.5.2 asks you to determine whether earlier results were adversely affected and to act. If suspect product may have reached the customer, tell them directly before they find it in the records, and follow the notification terms in your quality agreement.
Is a NIST traceable certificate enough for my customer?: Only if their requirements stop at traceability. NIST's policy says the provider of a result has to support its own traceability claim, and NIST does not certify the claims of other organizations. A customer that requires accredited calibration looks for the accreditation mark and a scope that covers the calibration, not just the words NIST traceable.
Do I have to send my whole calibration register?: Not unless your agreement says so. Send the records for the instruments and the period they asked about. A register extract that lists each instrument with its certificate number, calibration date and due date lets them choose which certificates to review.

Put it into practice

Got a gage list? Send it over and we load it for you, usually in a couple of business days. Free on every plan. Then log every calibration to a tamper-evident audit trail and produce records on demand.

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Axiospec is a documentation and workflow tool. It helps you keep clean, traceable, audit-ready records. Certification depends on your own processes, scope and assessor.