Switching packaging suppliers, or bringing on a new one for a growing product line, is a decision most procurement teams get only one real chance to do carefully. Once volume commitments are in place, correcting a bad fit becomes expensive and slow. A structured audit before signing avoids most of the problems that surface later.
Start With Capacity, Not Just Capability
A supplier can make an excellent sample and still struggle to deliver consistent quality at production volume. Ask specifically about current utilisation and how your expected volume fits into their existing schedule, rather than assuming capability at small scale translates directly to capability at scale.
Request Real Production Samples
Samples made specifically for a pitch are not the same as what comes off a production run on a busy Tuesday. Ask for samples pulled from actual production batches, and if possible, from more than one batch, to see genuine run-to-run consistency rather than a single best-case example.
Reviewing a supplier's range of PET preforms alongside their closures and jars gives a fuller picture of whether they can support your full packaging system rather than just one component.
Ask About Quality Control, Specifically
Do not accept "we have a quality process" as an answer. Ask what is measured, how often, what the rejection criteria are, and what happens when a batch fails internal checks. Specific answers indicate a mature process; vague answers usually indicate the opposite.
Understand Their Supply Chain Resilience
Ask what happens if a key raw material becomes scarce, or if a piece of equipment goes down. Suppliers with backup sourcing arrangements and documented contingency plans are considerably less likely to leave you with an unexplained gap in supply during peak season.
Check References From Similar-Volume Clients
A reference from a much smaller client tells you little about how a supplier performs at your scale. Ask specifically for references from clients of comparable volume and, ideally, in a similar product category.
Put It in Writing
Once you are satisfied, document the agreed specifications, tolerances, and quality expectations clearly before the first production order. A clear written record is what protects both sides when questions arise months into the relationship.