How Much Does Slack Spend On AWS?

The Slack messaging app is popular because it is easy to use, affordable, and highly customizable. With Slack, you can collaborate in teams and with colleagues in real-time, accessing files from anywhere.

Slack is also widely used because it enables users to create and join channels. In addition, it integrates with multiple apps and services, working seamlessly with the tools you already use.

Slack also offers cost-effective pricing plans, and its cloud infrastructure story is a compelling case study in how a SaaS company can scale rapidly on AWS while keeping costs in check. So how much does Slack actually spend on AWS, and what can your organization learn from their approach?

Does Slack Run On Amazon Web Services (AWS)?

Slack has been using AWS cloud infrastructure since 2009 when it was still Tiny Speck, then a chat tool for a gaming platform. As Richard Crowley, Director of Operations at Slack once said, AWS was the only viable option then.

Slack no longer uses AWS for lack of alternatives. According to Crowley, AWS was good for them and there was no need for Slack to leave years later.

The goodness he was referring to was how AWS enabled Slack to be highly scalable without building and maintaining its own infrastructure locally.

In June 2020, Slack and AWS announced a renewed deal where Slack reiterated that it would continue to use AWS as its “preferred cloud provider”. AWS also announced it would offer Slack as an option for all its internal communications.

It appears that this deal is going to last for a while, as Slack and AWS seem to be making a dig at Teams and Azure, which compete with Slack and AWS respectively as Microsoft’s communication tool and public cloud platform.

Even after Salesforce acquired Slack for $27.7 billion in July 2021, the AWS relationship has remained intact. Slack continues to run its core infrastructure on AWS, and the partnership has deepened with integrations like AWS Chatbot for DevOps workflows within Slack channels.

How Much Does Slack Spend On AWS?

Slack’s last publicly confirmed AWS spend was at least $85 million per year — or about $7.08 million per month — based on an SEC filing for the fiscal year ending January 31, 2022. Slack committed to spending at least $425 million over five years through April 2025, according to an SEC filing. That commitment period has now expired, and current spending figures are no longer disclosed separately since the Salesforce acquisition.

That $85 million annual figure represented at least $35 million more per year than Slack’s previous AWS commitment of $50 million annually.

In April 2019, Slack said in an SEC filing that it was committed to spending $250 million through 2023. That meant, Slack would spend $50 million per year on AWS services. More specifically, Slack would spend that much on “processing and delivery infrastructure”.

Based on the $50 million per year figure, Slack’s AWS spend accounted for 12.5% of its annual revenue for 2019 — and about 10% of its operating expenses. According to Slack, it generated $400.6 million in revenue in 2019, an 82% increase, but suffered a $138.9 million net loss.

According to the new owner Salesforce, Slack’s $85 million AWS expenditure for the fiscal year ended January 31, 2022 represented 5.7% of its estimated $1.5 billion revenue at the time. However, Slack’s revenue has grown substantially since then. Salesforce CEO Marc Benioff stated in April 2026 that Slack revenue is expected to hit $3 billion this year, having tripled since the acquisition. If Slack’s AWS spend has scaled proportionally, the company could be spending upwards of $170 million annually on AWS infrastructure today — though no public filings confirm this.

What Cloud Services Does Slack Use?

Slack’s architecture is based on several AWS services, including the following major ones:

Credit: An illustration of how AWS Chatbot enables chats in Slack.

Besides those AWS services, Slack also uses the Redis data structure server, the Squid caching proxy, the Apache Solr search tool, and a MySQL database.

Slack’s new platform relies heavily on AWS cloud infrastructure to deliver its services.

How Has Slack’s Cloud Architecture Evolved?

Slack’s infrastructure has come a long way from its early days of a handful of manually provisioned EC2 instances in a single AWS account. As the platform scaled to support millions of daily users, the Cloud Engineering team tackled several significant architectural challenges.

One of the biggest pain points was managing hundreds of AWS accounts with overlapping CIDR ranges, which made VPC peering increasingly difficult. Slack’s engineering team built a new network architecture (internally called Whitecastle) that used AWS shared VPCs and Transit Gateway inter-region peering. This approach centralized IP space management, eliminated rate-limiting issues caused by having all resources in a single account, and enabled seamless connectivity across multiple AWS regions.

The new architecture supports three environments — sandbox, dev, and prod — with automated network testing that validates cross-region connectivity in real time. This kind of infrastructure maturity is what allows Slack to maintain high availability for its 47 million daily active users while keeping operational overhead manageable.

For engineering teams evaluating how to structure their own multi-account AWS environments, Slack’s evolution from monolithic single-account setups to shared VPCs and Transit Gateway offers a practical blueprint. And understanding the true cost of EC2 instances across that kind of distributed architecture is where tools like CloudZero become essential.

Is Slack Profitable Now?

Before its acquisition, Slack was not profitable. In its final full fiscal year as an independent company (FY2021, ending January 31, 2021), Slack reported a $292 million net loss, an improvement from a $567 million loss in FY2020.

In FY2021 (ending January 31, 2021), Slack Technologies generated $902 million in revenue, a 43% increase over the previous year’s $630 million.

In Q1, 2022, Slack generated $273.4 million in revenue, a 36% year-over-year growth. There were no further reports for 2022. Salesforce has since confirmed it won’t be disclosing individual revenue for its acquired companies, such as Slack and Tableau.

By 2023, Slack had grown to 200,000 paid customers. As of 2025, estimates from Statista and DemandSage place Slack at roughly 47.2 million daily active users and 79 million monthly active users. And in April 2026, Salesforce CEO Marc Benioff reported that Slack’s revenue is on track to reach $3 billion for the year — a figure that suggests the product line is in a far stronger financial position than its standalone years, even if Salesforce does not disclose Slack-specific profitability.

What Cloud Cost Optimization Techniques Does Slack Use?

Slack Technologies employs several native AWS cost-optimization techniques, including rightsizing resources to workloads, AWS Reserved Instance pricing, Spot Instance pricing, and AWS Auto Scaling.

There is a tight integration between Slack’s architecture and AWS. Picture this illustration from AWS itself:

Credit: An illustration of Slack architecture on the AWS public cloud platform.

That implies the company also uses cost allocation tags to track AWS usage by department, project, or other criteria. In addition, Slack leverages AWS Trusted Advisor to identify and optimize potential cost savings.

In the same way, Slack sends detailed cloud spend reports to other companies, it also sends it to its teams, like this:

Credit: Slack sends detailed CloudTrail Events and CloudWatch Alarms to specific team members for further analysis.

The company’s network architecture evolution also plays a role in cost management. By consolidating from hundreds of individual AWS accounts with separate VPCs to a shared VPC model, Slack reduced the administrative overhead of managing CIDR ranges, peering connections, and per-account rate limits. Simplifying infrastructure management is itself a form of cost optimization — it reduces the engineering hours spent on operational toil rather than product development. For organizations facing similar challenges, understanding SaaS cost of goods sold (COGS) at a granular level is the first step toward identifying which infrastructure costs are truly driving value.

How Does Slack Monitor Its Cloud Spend?

Slack uses Amazon CloudTrail to monitor logs related to Amazon EC2 instances and Amazon Route 53 for DNS management. The company has also built custom monitoring for its network infrastructure, including an internal Go application that validates cross-region connectivity and writes results to CloudWatch dashboards visualized in Grafana.

However, Slack does not publicly detail how it continuously monitors its AWS cost data at a granular level. For organizations that want the kind of real-time cost visibility that native AWS tools struggle to provide, a dedicated FinOps platform can fill the gap.

How to View, Understand, And Control Your AWS Spend The Easier Way With Slack + CloudZero

Slack + CloudZero is a match made in cloud cost optimization heaven.

CloudZero provides real-time cost allocation, and allocates 100% of your cloud spend in a few hours — not days or weeks.

You do not need cost allocation tags here, so CloudZero saves you the hassle of maintaining perfect tags, unlike native AWS cost tools like AWS Cost Explorer.

Yet, CloudZero will accurately surface your tagged, untagged, and untaggable resources, as well as the cost of individual tenants within a shared environment.

In addition, CloudZero helps you understand your per-unit costs instantly. There are 12 unit cost dimensions available by default, including cost per customer, cost per team, cost per project, and cost per feature.

Also, you can also add custom dimensions to understand your cloud costs in the context that is most relevant to your business, such as cost per customer per feature.

You can take advantage of this granularity across your multi-cloud environment; AWS, Azure, GCP, Oracle Cloud as well as across platforms like Snowflake, Kubernetes, Databricks, Datadog, New Relic, MongoDB, and more.

Ultimately, Slack + CloudZero delivers timely, noise-free, and context-rich cost anomaly alerts straight to exactly who needs to see it, when they need to see it.

This enables you to quickly get to the root cause of the cost anomaly and stop it before it becomes a budget overrun. You can also get finance and other stakeholders involved with detailed alerts to prevent a surprise cloud bill.

Companies across SaaS, fintech, and security use CloudZero to capture, understand, and optimize their cloud costs — and the same visibility that would help a company like Slack understand its AWS spend at a granular level is available to organizations of any size.

to experience CloudZero for yourself.

Software and pricing information last verified May 2026. Features, pricing, and availability may have changed. Please verify current details with vendors before making decisions.

Author Spotlight

Cody Slingerland

Cody Slingerland, a FinOps certified practitioner, is an avid content creator with over 10 years of experience creating content for SaaS and technology companies. Cody collaborates with internal team members and subject matter experts to create expert-written content on the CloudZero blog.