Carbon accounting for technology and SaaS companies from data you already have

Last updated July 2026. Technology and SaaS companies are being asked for an emissions number from three directions: California SB 253 pulls in companies over $1 billion in revenue doing business in the state, enterprise customers push carbon questionnaires onto the software vendors in their own Scope 3, and investors increasingly ask portfolio companies for a footprint. The good news for a tech company is that it barely has a Scope 1 or 2 to speak of, so almost the whole inventory can be built from spend. Cloud bills, travel and expense data, and the accounts payable file that lists every SaaS subscription, contractor and hardware purchase are the raw inputs, and our carbon accounting software classifies them into a scope-by-scope inventory with the evidence attached.

A software company's footprint is lopsided in a way that actually makes it easier to measure. Scope 1 is usually tiny: perhaps a backup generator or company vehicles, often nothing at all for a cloud-native firm with leased offices. Scope 2 is the electricity for your offices, and if you run your own data center, the power that draws. Scope 3 is where almost everything sits, often 70 to 90% or more of the total. For Salesforce, a large public example, roughly 92% of emissions fall in Scope 3, and purchased goods and services is the biggest slice. The dominant lines for most tech companies are purchased cloud and data-center services, purchased software and professional services, business travel, employee commuting and remote work, and capital goods such as laptops and servers.

Because a tech company's footprint is almost entirely spend-driven, the Scope 3 reporting screen is not a preliminary step here, it is most of the inventory. A coarse first pass over the AP file tells you whether cloud, travel or professional services dominates before you invest in provider-level data. The full procedure, with the EPA factors, is in our guide to calculating Scope 3 from spend.

You measure cloud emissions two ways, and use both. The precise route is provider data: AWS, Microsoft Azure and Google Cloud each publish a customer carbon footprint tool that reports the emissions of your actual usage, and AWS now includes Scope 3 data. The fast route is spend-based: apply an emission factor to your cloud invoices to get a screening figure that covers providers without a tool. Start with the spend screen to size the line, then bring in provider data for your largest cloud vendors so the number reflects your real usage rather than an industry average.

More are every year. A US technology company over $1 billion in revenue that does business in California must report Scope 1 and Scope 2 under SB 253, with a first deadline of November 10, 2026 and Scope 3 following in 2027. Below that threshold, the request almost always arrives from a customer: enterprise buyers report the software they use in their own Scope 3, so they push carbon questionnaires onto their vendors, and investors ask portfolio companies for a footprint. Either way the deliverable is a defensible Scope 1, 2 and 3 number with evidence behind it, and for a tech company that number is mostly a well-classified spend file.

For related sectors, see carbon accounting for manufacturing, logistics and healthcare. For the vendor landscape, see best carbon accounting software and the enterprise carbon accounting overview. If your reporting trigger is specifically California, SB 253 reporting software covers that regime in full.