The Quality Inspector's Checklist: How to Vet Packaging Suppliers (Without Getting Burned)

Look, I'm the guy who says "no." Quality/Brand compliance manager at a consumer goods company. I review every packaging component—films, pouches, labels—before it reaches our production line. That's roughly 200 unique items annually. And I've rejected about 12% of first deliveries in 2024 alone, mostly due to spec deviations vendors swore were "within tolerance." That initial misjudgment cost us real money. When I first started, I assumed a detailed PO was enough. A few $20,000+ reworks later, I learned the hard way that vetting the vendor is as important as vetting the specs.

This checklist is for anyone sourcing packaging—flexible films, healthcare barriers, medical device trays—where a millimeter off can ruin thousands of units. I'll give you the steps we use. It's not glamorous, but it'll save you from the headaches I've had.

When to Use This Checklist

Use this when you're evaluating a new supplier or re-qualifying an existing one for a critical project. It's overkill for a one-time, non-critical order, but it's essential for anything that touches your product's safety, shelf life, or brand perception. I'm talking about barrier packaging for food, sterile medical device packaging, or any primary consumer-facing material.

Here's the thing: I recommend this process for strategic partnerships. But if you're dealing with a simple, off-the-shelf corrugated box order, you can probably skip a few steps. Honesty builds trust—this is for the 80% of cases where packaging really matters.

The 5-Step Vendor Vetting Checklist

Step 1: Scrutinize the Capabilities Sheet (Beyond the Marketing)

Everyone sends a glossy capabilities PDF. Your job is to read between the lines.

What to do: Don't just file it. Cross-reference every claimed capability with a specific question. They say "healthcare packaging expertise"? Ask for the last 3 projects in your exact niche (e.g., Class II medical device blister packs). They mention "barrier technology"? Request the ASTM F1929 test results for oxygen transmission rate on a material similar to what you need.

The check point: Can they provide evidence—not just case studies, but test reports or batch records—for the claims relevant to you? If they hesitate, that's a red flag. From the outside, a big portfolio looks impressive. The reality is, a supplier might be a leader in snack bags but have zero real experience with pharmaceutical-grade foil laminates.

I should add that for companies like Bemis (now part of Amcor), their healthcare and specialty films division is a legit strength. But even then, you need to verify their specific plant can handle your job. What most people don't realize is that large packaging conglomerates have dozens of facilities with varying capabilities.

Step 2: Demand a Pre-Production Sample Protocol

This is the step most people ignore. They approve a digital proof and think they're done. Big mistake.

What to do: Before signing any contract, get in writing their process for pre-production samples. It must include: 1) Samples from actual production machinery (not a lab printer), 2) A checklist of what they'll measure (seal strength, ink adhesion, critical dimensions), and 3) Who pays for these samples and the timeline.

The check point: Do they have a formal sample approval workflow, or do they just "send something over"? In 2022, I implemented a mandatory sample protocol after a vendor used a different film gauge for production than they showed us in samples. The defect wasn't visible until the filling line jammed, ruining 8,000 pouches.

Real talk: A vendor pushing back on this is a vendor who cuts corners.

Step 3: Audit Their Change Management Process

Things change. A resin supplier discontinues a material. A printing plate wears out. The question is how they handle it.

What to do: Ask this directly: "Walk me through your process if a raw material becomes unavailable and you need to substitute something." Listen for key elements: 1) Immediate customer notification, 2) Submission of new material specs and test data, 3) A new round of pre-production samples, and 4) A formal change approval document requiring your sign-off.

The check point: Is their process proactive and transparent, or reactive and hidden? I don't have hard data on industry-wide practices, but based on our audits, maybe 30% of suppliers have a robust, documented change system. The others "make it work" and tell you later. That's how you get a non-compliant material in your medical package.

Per FTC guidelines (ftc.gov), material substitutions that affect product performance or compliance must be disclosed. A good vendor's process will reflect this.

Step 4: Decode the Quote & Terms

Here's something sales reps won't always highlight: the cost drivers and the risk clauses.

What to do: Line-item scrutiny. If the quote just says "custom film pouch," it's insufficient. Demand a breakdown: material (e.g., PET/AL/PE laminate), printing (number of colors, process vs. CMYK), converting (seal type, die-cut shape), and testing (in-house vs. third-party). Then, go straight to the terms. Look for: 1) Liability limits for consequential damages (like your production downtime), 2) Who owns the tooling (plates, dies), and 3) Payment terms for incremental changes.

The check point: Are the terms balanced? A supplier who caps their liability at the value of the shipment isn't sharing the risk of a failure that shuts down your line. Negotiate this. In our $18,000 project last year, we got them to raise the liability cap. It took an extra call, but it was worth it.

Oh, and about pricing: Business packaging quotes can vary by 40% for identical specs (based on our Q4 2024 bid process). The cheapest quote often—but not always—omits something.

Step 5: Conduct a Site Visit or Virtual Audit

If the order volume justifies it, see where your product will be made. If not, a virtual audit is non-negotiable.

What to do: Request a live video walkthrough of the production floor relevant to your job. Don't just look at the shiny machines. Ask to see: 1) Raw material storage (is it clean, controlled?), 2) Quality control stations (are gauges calibrated, with tags showing dates?), 3) The line clearance procedure between jobs, and 4) How they handle non-conforming material (is there a clearly marked quarantine area?).

The check point: Is there a culture of quality, or just a QC department? You can feel it. Are operators following posted procedures? Is the floor organized? When I visited a supplier in 2023, I saw their ink viscosity was checked and logged every hour. That told me more than any certification document.

Common Mistakes & Final Notes

Mistake 1: Rushing the process. Vetting takes time. Building it into your project timeline is crucial. A rushed vetting is a future quality incident waiting to happen.

Mistake 2: Not involving Quality upfront. Get your quality team on the first call. Their questions are different from Procurement's.

Mistake 3: Assuming big brand = perfect fit. A major player like Amcor/Bemis has vast resources, but you might be a small fish in a big pond. Ensure you know who your direct contacts are and their escalation path.

This process was accurate based on our practices as of Q1 2025. The packaging industry evolves, especially with sustainability pressures. Always verify current certifications and ask about new material innovations. And remember—your operator's manual for any critical equipment, including packaging machinery? Store it digitally in a shared drive the whole team can access, not in a binder on someone's shelf. You'd be surprised how often that simple thing gets overlooked until a midnight line stoppage.

Following this checklist won't guarantee zero problems. But it'll filter out the vendors most likely to cause the expensive ones. And that's the whole point.