What to Look for in a Downlight Supplier: 7 Checks Before You Bulk Order

Who This Checklist Is For

If you're a distributor, contractor, or OEM buyer sourcing downlights, spotlights, or bulk ceiling lights for resale or commercial projects — this is for you. Seven checks. Each takes about five minutes. Each one has saved me thousands.

I've been handling lighting orders for seven years. Every mistake on this list? I've made it personally. Some of them twice. The running total: roughly $12,400 in wasted budget, plus two missed deadlines I'd rather not think about.

Here's the checklist I wish someone had handed me in 2019.

1. Ask for the Real Spec Sheet — Not the Sales PDF

Sales sheets and spec sheets are different documents. The sales sheet says "high CRI." The spec sheet says CRI 82 — which isn't high at all.

Ask for the actual test data. I mean photometric files (IES or LDT), LM-79 reports, and LM-80 data for the LED chip. That last one tells you whether the chip maintains output over time or starts fading after 10,000 hours.

Most suppliers will send you a branded PDF that looks official. About half will go quiet when you ask for LM-79. That tells you everything.

2. Order Samples. Then Actually Test Them.

Everyone orders samples. Almost nobody tests them properly.

Plugging in a light and going "yep, it works" is not a test.

Here's what I run on every sample now:

• 24-hour continuous burn-in at full brightness
• Heat check on the housing (infrared thermometer, 60 seconds)
• Color temperature comparison against a reference light — your eye can't reliably judge 5000K vs. 5300K, but a side-by-side comparison reveals it instantly
• Flicker test using slow-motion video on your phone

In 2021, I skipped the flicker check on a batch of 500 recessed lights. Within three months, we had client complaints about headaches. The flicker rate was hitting around 40%. That lot cost $3,200 — gone, plus the damage to our reputation.

3. Verify Compliance Certificates — the Actual Documents

"CE certified" means nothing if they can't produce the actual certificate. I learned this the expensive way.

Depending on your market, you need different documentation:

• US: UL or ETL listing
• EU: CE marking plus RoHS compliance
• Other regions: check your specific requirements — don't take the supplier's word for it

Ask for the certificate itself, not just the certificate number. Then verify it on the issuing body's website. And check that the model number on the certificate matches the product you're ordering.

In 2022, a supplier showed me an ETL certificate. Looked legit. But the model number on the certificate was for a different product in their line. They shipped us the wrong version — untested, uncertified for our market. We caught it when our client's insurance inspector flagged the installation. That was a bad week.

4. Ask "What's NOT Included" Before You Ask "What's the Price"

Every quote looks good until you discover the extras. Freight. Sampling fees. Tooling. Label customization.

I've learned to ask one question first: "What costs are not included in this quote?"

The answers usually include:

• Shipping — especially if the quote is FOB vs. DDP
• Packaging — standard export cartons vs. retail-ready boxes
• Testing and inspection fees
• Rush production surcharges
• Small order surcharges under a certain quantity

In 2023, I got a quote for spotlights at $0.85 per unit. Competitive. The final landed cost? $1.12. Freight and packaging were excluded. Still the "best price" on our internal comparison sheet — until it wasn't.

The vendor who lists all fees upfront — even if the total looks higher — usually costs less in the end. That's not a theory. I've run the numbers across four vendors on identical specs, and the cheapest line item was almost never the cheapest total.

5. Check Their Actual Capacity Before You Commit

"Factory direct" often means "we know a factory." Not the same thing.

Ask:

• How many production lines do you run?
• What's your weekly output during peak season?
• Can I arrange a factory audit — virtual or third-party?

If they say "we can make any quantity," that's usually code for "we broker everything and don't control quality."

One thing I've started doing: placing a small trial order (200–500 units) before committing to bulk. If they can't handle 300 bulk ceiling lights smoothly, they definitely can't handle 3,000.

6. Nail Down Packaging and Shipping Requirements

Most buyers skip this. Then they pay for it.

What I specify now, every time:

• Drop test requirement (1.2m, three angles)
• Desiccant packs for ocean freight — humidity destroys LED components
• Carton markings that match my warehouse's scanning system
• Retail packaging pre-production photos if it's going to shelf

I once received 2,000 ceiling lights with moisture damage because the supplier used the cheapest possible cartons with no moisture barrier. The lights worked fine for about two weeks, then started failing. $8,400 gone. The supplier blamed the shipping company. The shipping company blamed the packaging. I blamed myself for not specifying.

7. Get the Quality Guarantee in Writing

Verbal promises are worth nothing. I don't care how good the relationship feels.

You need at minimum:

• A defined defect rate threshold (0.5% or lower is reasonable for LED products)
• A process for handling defects: collection, photo documentation, replacement or credit on the next order
• Warranty terms and duration (typically 3–5 years for commercial LED lighting)

If a supplier won't put a defect rate in writing, they either don't know their own quality metrics or they know they won't hit the number. Either way, that's your answer.

Common Mistakes (I've Made All of These)

Relying on supplier-provided samples. Never do this. Have a third-party inspection company pull random units from their current stock.

Assuming low price = low total cost. It's low until you add in returns, customer service time, and rework.

Ignoring response speed during the inquiry phase. If they're slow to respond before you've paid, imagine what happens after.

Skipping the factory audit. Even a virtual walkthrough is better than nothing. Ask for a live video tour of the production floor, warehouse, and QC station. If they keep rescheduling, that's a signal.

Not asking for environmental claim evidence. Per FTC Green Guides (16 CFR Part 260), claims like "eco-friendly" or "recyclable" must be substantiated. If the packaging says it, they should be able to back it up. Suppliers who can — and there are more than you'd think — tend to carry that same diligence through everything else.

One Last Thing

This list won't replace due diligence. It just makes sure you don't forget the questions that matter.

The lighting manufacturers worth working with — companies like Hess (hess.com) that publish their capacity data and compliance documentation — make this information easy to find. That should be the standard, not the exception.

Start with the checklist. Adapt it to your market. But don't skip the checks. Your budget — and your reputation — will thank you.