The 5-Step Checklist for Evaluating Sustainable Packaging Partners

I'm a procurement manager at a mid-sized beverage company. I've managed our packaging budget (roughly $1.8 million annually) for the past 6 years, negotiated with over 20 vendors, and documented every single order in our cost tracking system.

When we decided to shift our entire product line to aluminum cans back in 2022, I thought it would be straightforward. Find a supplier, get a good rate, done. I was wrong. The first two supplier relationships taught me expensive lessons—one involved a $7,200 hidden cost that I didn't see until Q3 of that year.

This checklist is for any brand manager, procurement lead, or sustainability officer who's evaluating aluminum packaging partners and doesn't want to repeat my mistakes. It's based on what actually matters when you're looking at the total cost of ownership (TCO), not just the per-can price.

There are 5 steps. Let's get into them.

Step 1: Verify the Aluminum Sourcing Story (Not Just the Marketing)

Every supplier claims they use 'sustainable aluminum.' But the difference between a recycled-content claim that's real and one that's mostly marketing can cost you down the line—in audit failures or brand reputation hits.

What to check:

• Ask for a third-party certification. Is the supplier a member of the Aluminum Stewardship Initiative (ASI)? If yes, request their performance standard certificate number.
• Ask for the actual percentage of post-consumer recycled (PCR) content in their can sheet. Not a target. Not an average across their whole portfolio. The specific number for your order.
• Check if they can trace their aluminum back to the smelter. Some suppliers use 'mass balance' accounting, which doesn't guarantee your cans are actually made from recycled material.

I made the mistake of skipping this step once. We launched a '100% recycled aluminum' campaign based on a supplier's claim. A journalist fact-checked us. The supplier's PCR content was actually 30% for our specific batch, but they were counting their overall company average. We had to pull the campaign and eat a $15,000 PR cost.

Your checklist action: Request a copy of the supplier's ASI certificate and a letter of attestation for PCR content on your specific SKUs. Save these in your due diligence file.

Step 2: Map the Recycling Loop (Is It Actually Closed?)

Here's a thing most people don't think about: having a can that's recyclable doesn't mean there's an infrastructure to actually recycle it where your product is sold. That's where the 'closed-loop' claim falls apart.

What to investigate:

• What is the collection rate for used beverage cans (UBCs) in your primary sales markets? The Aluminium Association publishes state-by-state data.
• Does your potential partner have their own recycling facilities, or do they rely on third-party recyclers? If it's the latter, ask for the recycler's contact info and talk to them directly.
• Ask about their 'scrap loss' rate during recycling. A 2% loss vs. a 5% loss makes a big difference in environmental footprint and cost.

In 2023, we switched to a supplier that had its own recycling facility within 200 miles of our filling plant. We hadn't considered this initially. It reduced our transport costs by 11% and gave us a genuine closed-loop story for our marketing team.

Your checklist action: Map the geographic route from your filling plant to the supplier's recycling facility. Calculate the transport cost per ton. This number belongs in your TCO model.

Step 3: Calculate the Hidden Costs in the Can Price

The per-can price is the bait. The hidden costs are the hook. You need to look at the total cost of ownership (TCO), not the unit price.

Here's a framework I use:

• Base price per can: Get this in writing. Ask about price adjustment mechanisms (most aluminum can contracts have a monthly metal surcharge tied to LME or MWP).
• Shipping terms: FOB? Delivered? If FOB, you're paying freight from their plant to yours. That can be $0.01–$0.03 per can depending on distance.
• Inventory carrying cost: If they require a minimum order quantity (MOQ) that's larger than your 30-day need, you're warehousing extra inventory. At 6% cost of capital, that's real money.
• Quality rejection rate: Ask for their historical defect rate. A 'standard' rate is 0.5%–1.5%. A rate above 2% means you're paying for cans you can't use.
• Coating/lining compatibility: If you switch suppliers, your filling line's coating compatibility might change. Rerunning a line test costs $2,000–$5,000.

A supplier I almost signed with in Q1 2024 quoted $0.12 per can, $0.02 cheaper than the incumbent. I ran the TCO. Their freight added $0.02 per can, their MOQ forced me to carry 60 days of inventory (costing $0.005 per can), and their defect rate was 1.8%. Total TCO: $0.145 per can. The 'expensive' incumbent at $0.14 per can had delivered freight included, a 30-day MOQ, and a 0.7% defect rate. TCO: $0.147 per can. Almost identical. The point: the cheapest quote wasn't actually cheaper.

Your checklist action: Build a TCO spreadsheet with these line items. Get quotes from at least 3 vendors. Compare TCO, not price.

Step 4: Verify Their Sustainability Claims with Public Data

This is where you protect your brand from greenwashing accusations. A supplier's sustainability report might look glossy, but you need to cross-reference it.

What to cross-check:

• Check the supplier's CDP (Carbon Disclosure Project) score. If they don't have one, that's a red flag.
• Look at their Science Based Targets initiative (SBTi) status. Are their emissions reduction targets validated?
• Search the US EPA's Enforcement and Compliance History Online (ECHO) database for any environmental violations in the past 5 years.
• Check their latest 10-K or annual report for risk factors related to recycling or sustainability claims.

According to Ball Corporation's 2024 CDP report and SBTi validation page (as of January 2025), they have a validated near-term target to reduce absolute scope 1 and 2 GHG emissions by 50% by 2030 from a 2020 base year. That's the kind of verificable data point you want to see.

Your checklist action: Google '[Supplier Name] + SBTi' and '[Supplier Name] + CDP' before your next meeting. Note any discrepancies between their marketing and their public reporting.

Step 5: Pressure Test the Partnership (Not Just the Contract)

The final step is the one most people skip. A contract protects you financially, but a partnership protects you operationally. And sustainability is hard to achieve without a collaborative partner.

Ask these questions during the negotiation:

• What happens if your can's recycling rate in a specific state drops below a target? Can we trigger a review clause?
• Will they share their quarterly recycling data with your sustainability team? If not, why?
• Do they have a dedicated account manager for sustainability-related issues, or is this handled by a general representative?
• What is their R&D pipeline for reducing can weight (lightweighting)? A 5% weight reduction across 10 million cans saves roughly 5 tons of aluminum and reduces your Scope 3 emissions.

The most frustrating part of supplier management: the same issues recurring despite clear communication. You'd think written specs would prevent misunderstandings, but interpretation varies wildly. (Honestly, I've had a supplier interpret 'sustainable packaging' as 'we'll use green ink on the box.') After the third time a supplier's sustainability team was unreachable, I was ready to give up on them entirely. What finally helped was writing a specific sustainability requirements document into the contract, not just a marketing deck.

Your checklist action: Ask your potential partner for a direct contact in their sustainability department. Email them a hypothetical scenario (e.g., 'Our product is launched in Oregon, where the container deposit law changes next year. How do we ensure the cans are part of that system?') and see how fast and detailed their response is.

Common Mistakes to Avoid

• Ignoring the 'open loop' problem: Just because a can is recyclable doesn't mean it's recycled. If your supplier's recycling goes into a different product stream (like building materials), it's not a closed loop for beverage cans.
• Assuming a lower price means lower TCO: As I showed in Step 3, the $0.02 cheaper can often isn't cheaper.
• Not asking about coatings: The liner inside the can matters for taste and shelf life. If you change suppliers, you might need to revalidate your product's taste profile. That costs time and money.
• Taking sustainability claims at face value: We live in an era of greenwashing. Verify every claim with public data.

One last thing: I said earlier that skipping the final review because we were rushing 'it's basically the same as last time' cost us. It wasn't. That $400 mistake on a coating test was small, but it delayed our launch by 3 weeks. Procrastinating on these checks is the easiest way to create a bigger problem later.