Slack·SaaS / Digital Services·San Francisco, USA·Founded 2009·Last verified 31 May 2026
37
out of 100
Below expectationsPending Review

Slack has no independent sustainability reporting; all environmental data is buried in parent Salesforce's consolidated metrics. The company recently dropped absolute Scope 3 reduction targets in favor of intensity metrics—a hallmark greenwashing move. No Slack-specific emissions, waste, water, or nature data exists; renewable energy claims rest on market instruments, not additionality.

The calculation

Every score shows its working.

Same formula for every company. No curve. No private weighting.

SINK = (0.3 × Base + 0.7 × Performance) × Scale
Industry base impact
SaaS / Digital Services sector ceiling.
70 / 100
Performance score
Sum of the 10 rubric questions, scored 0–10 each.
38 / 100
Raw score
Weighted average before scale penalty.
(0.3 × 70) + (0.7 × 38) = 47.6
Scale penalty
Multiplier based on absolute emissions volume — physics-first.
× 0.82
Final score
Rounded. Below expectations.
37 / 100
The ten questions

Where Slack is strong, and where it isn't.

Strongest on Energy Source and Carbon Footprint — Operations (6/10, 4/10). Weakest on Water Impact and Resource Use & Waste (3/10, 3/10).

Where the evidence comes from

Every document used, listed.

10 sources used in this assessment. All publicly available. Each row shows which rubric questions it informed.

[1]Self-reported
FY25 Schedules of Environmental and Employee Metrics
2025
Q1Q2Q3Q8Q9
View →
[2]Third-party verified
SBTi Supplier Engagement Case Study: Salesforce
Unknown
Q2
View →
[3]Public record
Salesforce Quietly Drops Key Climate Goals to Cut Emissions
2024
Q3Q8Q10
View →
[4]Public record
Salesforce Shifted 2030 Climate Goals While Going All-In on AI
2024
Q3Q8
View →
[5]Self-reported
Salesforce Net Zero
Ongoing
Q4
View →
[6]Self-reported
Slack Step Up Declaration
Unknown
Q4Q8
View →
[7]Self-reported
Salesforce Sustainability
Ongoing
Q5Q9
View →
[8]Self-reported
Green Code: Software Development
Unknown
Q6
View →
[9]Third-party verified
The A-List of Climate Policy Engagement 2021
2021
Q10
View →
[10]Public record
Corporations Are Tanking America's Best Shot at Fighting Climate Change
Unknown
Q10
View →

If you believe a source has been misread or a newer version exists, submit a challenge.

Slack in context

Where Slack sits among saas / digital services peers.

Among the 35 major saas / digital services brands we've scored, Slack is tied =26th of 35, with 1 other.

=26/35
Slack's rank
46
Industry average
25
Industry low
74
Industry high
How this score has moved

Slack's score over time.

today

Score history begins 6 April 2026.

As Slack's score updates, the trajectory will appear here.

We're backfilling historical scores for FTSE 100 and S&P 100 companies over the coming weeks.

What's being contested

This score is not currently being contested.

Every challenge is published. We'd rather be corrected than wrong — that's the whole point.

No challenges submitted yet. If you have evidence that contradicts this score, you can challenge any question above — cite a public source and we'll review it.

About Slack

Slack is a cloud-based workplace messaging and collaboration platform founded in 2009 and headquartered in San Francisco. Acquired by Salesforce in July 2021, it serves millions of users globally. As a SaaS business, Slack has minimal direct environmental impact but lacks independent sustainability disclosure and operates under its parent's consolidated reporting.

Founded
2009
Headquarters
San Francisco, USA
Employees
~3,500
Annual revenue
~$2.3B
Company website ↗
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