ESG reporting has reached marketing budgets. Finance teams and sustainability officers are now asking the same question: what does each channel actually cost, measured in carbon per impression? The answer matters for scope 3 reporting, board-level sustainability disclosures, and the growing share of corporate procurement decisions that require documented environmental impact.
In February 2026, PPAI and ASI released a joint study conducted by independent research firm 51toCarbonZero that answered this question with full lifecycle methodology. The result: promotional products generate 0.7 grams of CO2 equivalent per memorized impression — tied with out-of-home advertising for the lowest of any channel measured, and eight times lower than digital display advertising at 5.6 grams. This post covers the full ranking, what drives it, how different promo categories perform, and where the carbon case honestly breaks down. It's part of Promolistic's industry research hub.
The full 7-channel ranking
The table below ranks seven advertising channels by CO2 per memorized impression, combining the PPAI-ASI joint study (February 2026) with PPAI's publicly available summary of its Carbon Cost of Attention research (March 2026). "Per memorized impression" is the key unit: it normalizes for how long each channel actually generates brand recall, not just how many exposures were purchased.
| Rank | Channel / Category | CO2e per 1,000 impressions (est.) | What drives it |
|---|---|---|---|
| 1 | Promotional products (overall) | 0.7g per impression | Full lifecycle amortized across retention window |
| 1 | Out-of-home (billboard / transit) | 0.7g per impression | Tied — infrastructure shared across thousands of views |
| 2 | Print advertising | ~1.5g per impression | Paper, ink, distribution logistics |
| 3 | Email marketing | ~2.1g per impression | One impression per send; low carryover |
| 4 | TV / radio broadcast | ~3.8g per impression | Broadcast infrastructure, production energy |
| 5 | Digital display + social media | 5.6g per impression | RTB, data centers, low viewability |
Source: PPAI-ASI joint study, conducted by 51toCarbonZero, February 4, 2026; per PPAI's publicly available summary of Carbon Cost of Attention, March 2026.
One finding that often surprises marketing teams: email doesn't top the channel ranking. Email generates one impression per send — even at low per-send carbon, the lack of carryover impressions pushes its per-memorized-impression figure well above physical promotional items that generate hundreds of recall events from a single unit of production.
On a per-campaign basis, the gaps are even more striking. A digital advertising campaign produces 0.87 metric tons of CO2e — 2.2x more than a promotional product campaign at 0.39 metric tons. A TV broadcast campaign produces 7.83 metric tons, equivalent to running 20 promotional product campaigns of the same budget.
One nuance: per-dollar-spent parity with digital holds — both channels produce approximately 0.2g CO2e per dollar invested. The promo advantage is at the impression level, not the cost level.
How per-impression carbon is calculated
The PPAI-ASI joint study used full lifecycle assessment (LCA) methodology, measuring emissions from materials sourcing through production, delivery, and end-of-life disposal. That framework captures embodied carbon in physical products and energy carbon in digital delivery within the same methodology.
"Per memorized impression" is the correct normalization because it accounts for how long each channel actually delivers brand recall. A promotional travel mug used every morning generates impressions daily for months. A digital display ad generates one impression per energy-intensive serve, with no carryover.
For a physical item, the math is: total lifecycle CO2 ÷ total impressions over use life. A stainless tumbler used 4–5 times per week for 18 months accumulates thousands of impressions from its manufacturing footprint. Each individual impression becomes very cheap from a carbon standpoint. A branded canvas tote generating 4,900 lifetime impressions distributes its embodied carbon across every use.
For digital channels, the math includes: data center energy, real-time bidding (RTB) compute, content delivery network load, and device rendering energy. The per-impression figure worsens as viewability rates decline — a meaningful share of served digital impressions are never actually seen, but the energy cost is real regardless.
Carbon by promotional product category
The 0.7g CO2e overall figure for promotional products masks significant variation across categories. The carbon performance of a promotional item depends entirely on how long the recipient keeps it and how often they use it.
| Category | Per-impression CO2e | What drives it |
|---|---|---|
| rPET tote bags | Under 0.3g | Recycled-material manufacturing + 4,900 lifetime impressions |
| Reusable insulated drinkware | Below 1g | Daily use 18+ months amortizes steel/production carbon |
| Recycled cotton apparel | ~0.5–1g | Lower material carbon; high visibility impressions |
| Branded bags (standard) | ~1–2g | 150+ uses over 18 months |
| Tech accessories | ~2–3g | Higher manufacturing carbon; daily use offsets if retention holds |
| Single-use promotional novelties | ~5–8g | Manufacturing carbon divided by very few impressions |
Per the PPAI-ASI joint study (February 2026) and PPAI's publicly available summary of Carbon Cost of Attention (March 2026).
rPET items (made from recycled plastic bottles) reduce material-stage carbon by up to 79% versus virgin polyester equivalents. Bamboo accessories and recycled cotton apparel also score well. These are the items where per-impression carbon falls furthest below the 0.7g category average.
Tech accessories have higher starting-point manufacturing carbon than fabric or stainless steel — circuit components, lithium cells, and plastic housings carry meaningful embodied carbon. But daily-use frequency and 18–24 month retention periods offset that. The category risk: tech accessories that don't work well get discarded immediately, generating almost zero impressions from their production footprint.
Single-use novelties — plastic keychains, stress balls, short-lifecycle items — are the category where the sustainability case for promotional products collapses. Manufacturing and disposal emissions divided by a very small number of impressions produces a per-impression figure that can exceed digital display. An internal sustainability audit that categorizes all branded merchandise together obscures this material difference.
Eco-friendly totes and bags with recycled-material options
Foldable Tote Bag Credit Card Size - Everless
Custom Printed Tote Bag Cotton Canvas Market - 13¾ in
Custom Printed Tote Bag Cotton Tie Dye Candy - 14 x 16 in
Custom Printed Tote Bag Oxford Polyester Food Mat - 8½ x 12¼ in
Custom Printed Tote Bag Cotton Canvas Garden - 8 x 8 x 10 in
What this means for ESG-driven procurement
Marketing teams operating under corporate sustainability mandates can cite the PPAI-ASI joint study directly in budget justifications. The argument is quantitative, not ethical: "We chose branded merchandise because the February 2026 PPAI-ASI joint study, conducted by independent firm 51toCarbonZero, places it at 0.7g CO2e per memorized impression — eight times lower than digital advertising."
Material certification provides the audit trail ESG reporting frameworks require. Global Recycled Standard (GRS) covers recycled content. FSC covers paper and wood. GOTS covers organic cotton. Without those certifications, a "recycled" claim on a promotional product may not meet the documentation threshold for scope 3 reporting.
Before citing carbon claims in an external ESG report, ask your supplier for a lifecycle assessment or product carbon footprint summary for the specific items ordered, confirm material composition and recycled-content percentages, and get manufacturing origin and shipping distance data. The PPAI-ASI joint study gives you the channel baseline. Supplier-specific data confirms whether your actual order meets it.
ASI's 2026 Ad Impressions Study adds a brand perception dimension: 74% of consumers say they'd feel more favorable toward a brand that gives eco-friendly promotional products. That's a marketing argument on top of the carbon argument — brand perception lift that digital channels can't replicate in any form.
High-retention drinkware — lowest CO2 per impression in the catalog
Silicone Key Ring Tumbler Shaped - 3 in
Tumbler Sling rPET Neoprene 40 oz Pouch - 4 x 9 x 3 in
Glass Tumbler Borosilicate with Silicone Sleeve - 32 oz
Insulated Tumbler Recycled AS Double Wall with Straw - 40 oz
BruMate Togosa Insulated Tumbler Dual Lid System - 50 oz
Where the carbon case breaks down
The PPAI-ASI study is rigorous — independent research, full lifecycle methodology, multi-market validation. But there are real limits to what the carbon ranking can and can't justify.
Where the comparison holds:
- Per-impression carbon is real and documented for durable items. One manufacturing run generates impressions for months without ongoing energy cost.
- Material certification (GRS, FSC, GOTS) provides the audit trail ESG reporting frameworks require. Digital channels don't produce equivalent documentation.
- 84% of consumers keep branded bags for at least a year and 92% use them monthly, per ASI 2026 data. At that retention rate, embodied carbon is distributed across thousands of actual impressions.
Where the comparison has real limits:
- The study measures brand recall impressions — not clicks, conversions, or direct response outcomes. Digital advertising's per-impression carbon disadvantage doesn't eliminate its performance advantage in lower-funnel tactics. Retargeting, lead generation, and e-commerce conversion are not areas where promotional products compete.
- Per-dollar parity with digital means the carbon advantage only appears at the impression level. Teams with tight cost-per-acquisition targets can't swap digital for merch and expect the same conversion volume.
- Single-use items that get discarded immediately generate embodied carbon for zero impressions — net negative on the per-impression metric. The carbon advantage depends entirely on the recipient keeping and using the product. Quality and utility aren't just marketing priorities here — they're environmental ones.
- Large orders shipped by air freight can significantly exceed the 0.39 metric ton per-campaign baseline. Per-product carbon varies by material sourcing and shipping distance.
The conclusion isn't "promo beats digital on carbon in every case." It's that high-utility, durable items selected for a recipient who will actually use them often outperform digital on the per-impression metric — and eco-material options improve the math further. For the broader context on branded merchandise and its role in the marketing mix, see the branded merch vs digital ads recall post and the industry research hub.
Frequently Asked Questions
Sources
- PPAI / ASI Joint Study — Joint PPAI-ASI Study Finds Promo Among The Lowest Carbon Impact Advertising Channels, February 4, 2026. Conducted by independent research firm 51toCarbonZero. Read article
- ASI Advertising Specialty Institute — Landmark Study Shows Promotional Products Drive High Marketing Impact With a Low Carbon Footprint, February 4, 2026. Read press release
- PPAI Research — The Carbon Cost of Attention: Comparing Marketing Channels, March 2026. Per PPAI's publicly available summary. Read summary
- ASI Advertising Specialty Institute — 2026 Global Ad Impressions Study, January 2026. Read study
- The Ecologist — Digital Marketing's Carbon Footprint, March 5, 2025. Read article
- Mike Berners-Lee — How Bad Are Bananas? The Carbon Footprint of Everything, updated edition, 2020. Email carbon estimate: 0.3–4g CO2 per email sent.
