Science-Based Targets with Spend Data

Here’s the scenario: you’ve measured your company’s first carbon footprint, mostly with spend-based emission factors. The baseline is live, the board has applauded… and now asks for a science-based reduction pathway. Can a footprint built on pounds-spent really stand up to the Science Based Targets initiative (SBTi)? The answer is yes, provided you treat spend data as a springboard rather than a destination.

Below is a practical roadmap that small and mid-sized teams can follow to convert a spend-driven baseline into credible near-term science-based targets (SBTs) and a plan for continuous data improvement.

1 Map spend data to SBTi coverage rules

SBTi requires near-term targets that cover:

• ≥ 95 % of Scope 1 and 2 emissions.
• ≥ 67 % of total Scope 3 emissions, if Scope 3 exceeds 40 % of the corporate total. sciencebasedtargets.org

Your spend-based inventory already breaks down Scope 3 by purchase category (goods, services, travel, logistics). Calculate each category’s share of the total. If your top five categories represent two-thirds of Scope 3, they will form the target boundary. Record this coverage clearly; SBTi reviewers ask for the numbers.

2 Choose an appropriate target type

Spend-based data is typically less granular than activity data, so pick a target framework that tolerates improvement over time:

• Absolute reduction targets – straight percentage cut from baseline year (e.g. –42 % by 2030 in line with 1.5 °C). Recommended where spend patterns are stable.
• Economic intensity targets – emissions per £ value added or per tonne of production. Useful for fast-growing firms whose spend expands faster than headcount.

SBTi allows either approach as long as the reduction trajectory aligns with its 1.5 °C curves. Use the free SBTi Target Setting Tool to test which option yields a realistic glide-path with your current data quality.

3 Quantify the required cut using spend factors

With the baseline year locked, apply SBTi’s percentage reduction to each covered category. Example:

• Purchased goods & services 2024 baseline: 15 000 tCO₂e
• Target reduction: 42 % by 2030
• 2030 target: 8 700 tCO₂e

Repeat for all in-scope categories and add a buffer of 5-10 % to accommodate factor updates. Document the maths and store it with your baseline evidence; auditors will trace the chain from spend line to target figure.

4 Build a data-quality improvement ladder

Spend factors are acceptable for goal-setting, but SBTi expects methodological improvements over time. Plan three annual upgrades:

Year 1 – Supplier-specific intensity factors for your ten largest suppliers (total emissions ÷ revenue).

Year 2 – Product-level LCAs for strategic components or packaging.

Year 3 – Activity data (kWh, km, tonnes) captured via contract clauses or API feeds.

Publish the ladder internally so finance, procurement and suppliers see the destination. Progressively finer factors can tighten Scope 3 accuracy by 30-50 %, closing the gap between targets and real-world action.

5 Align cost forecasts with carbon reduction

Budgets speak louder than pledges. Translate the spend-based cuts into procurement and capex signals:

• Switch high-carbon spend – divert orders to suppliers with lower intensity factors and embed carbon clauses in RFPs.
• Fund data upgrades – allocate part of the sustainability budget to digital invoices, smart meters or supplier training.
• Create an internal carbon price – even a shadow price (£50/tCO₂e) highlights where spend is carbon-heavy and helps the CFO see the business case for change.

Link these levers to the reduction schedule so every pound of spend contributes to the emissions trajectory.

6 Submit targets and monitor quarterly

When documentation is ready, file your target with SBTi’s online portal. Once validated, pull spend data each quarter, refresh the footprint and plot progress against the 1.5 °C line. If emissions creep above the glide-path, prioritise the next data-quality upgrade or supplier switch in the ladder.

Common pitfalls and how to avoid them

• Waiting for perfect data – SBTi accepts spend-based baselines as long as you plan to improve quality. Start now, refine later.
• Ignoring exchange-rate swings – if you buy in foreign currencies, lock the baseline year FX rate for consistency.
• Mismatching factor versions – freeze one conversion-factor set per reporting year to keep glide-path maths stable.
• Setting ambition too low – SBTi rejects targets that fall short of 1.5 °C pathways; use its tool to check before submitting.

Quick wins you can action this week

• Tag your accounts-payable codes with SBTi coverage (% of Scope 3).
• Run the SBTi Target Setting Tool using your spend-based baseline.
• Draft a one-page supplier letter explaining how their emissions data feeds your target pathway.

Conclusion

A spend-based baseline is not a dead end - it is the starting line for credible, science-based climate ambition. By mapping spend data to SBTi coverage thresholds, choosing the right target type, and planning clear data-quality upgrades, finance and sustainability teams can set 1.5 °C-aligned goals today and sharpen accuracy tomorrow. The sooner you publish a target, the sooner every pound you spend starts working for the planet.

Emitrics automates the whole journey: importing ledger data, applying spend factors, and recalculating targets each time accuracy improves. Book a demo and see how easy science-based target setting can be.