Understand the SROI formula, work through an example, and test how assumptions change the estimated social value.
SROI, or social return on investment, is a framework for understanding and valuing outcomes in relation to the resources invested. It can express an estimate as a ratio—for example, an estimated $2 of social value for each $1 invested—but the evidence, stakeholder perspective and assumptions are essential to interpreting that number.
Social value is not necessarily cash received or a financial return to the investor. A valuation may represent an outcome that matters to stakeholders without creating a corresponding cash saving. Explain whose value is included and why a monetary estimate is useful for the decision.
SROI ratio = present value of adjusted outcomes ÷ value of inputs. The numerator should account for relevant effects that would have happened anyway, contributions from others, displacement and the duration of change. Future values may need discounting.
Do not confuse the ratio with net value. If adjusted present value is $150,000 and inputs are $100,000, the ratio is 1.5:1 and estimated net value is $50,000. A ratio below 1 does not automatically mean an intervention should stop; examine omitted outcomes, uncertainty, distribution and the purpose of the analysis.
Older SROI guides describe seven principles. Social Value International added an eighth principle, “Be responsive,” in 2021. Its current framework has eight. The numerical ratio should be read alongside those principles rather than treated as a standalone score. See SVI’s explanation of the addition.
In practical terms: involve the people affected, understand what changes, consider what matters, include material information, avoid claiming more than the evidence supports, explain the analysis, check it and use the learning to respond. Consult the current SVI standards and guidance for the formal framework.
A financial proxy borrowed from another setting may not represent the experience of your stakeholders. Keep the source, date, currency, geography and rationale with the value. If the fit is weak, show the uncertainty rather than hiding it inside a precise-looking ratio.
| Adjustment | Question | Practical caution |
|---|---|---|
| Deadweight | How much would have happened without this intervention? | Do not assume zero simply because no comparison data was collected. |
| Attribution | How much of the change relates to other contributions? | State whether the percentage means the share excluded or retained. |
| Displacement | Did the benefit replace or reduce a benefit elsewhere? | Check relevant effects beyond the immediate participant group. |
| Drop-off | How much of the outcome fades in later years? | Apply only when valuing outcomes over time; explain the assumed pattern. |
These are judgments requiring evidence. Applying four percentages is not the same as establishing causality. Social Value International’s “Do not overclaim” guidance discusses estimating deadweight and attribution. Read the guidance.
The following is a simplified, illustrative one-year example, not a customer result. It assumes 60 participants each experience an outcome valued at $2,000, for a gross value of $120,000. Inputs cost $45,000.
| Step | Calculation | Value |
|---|---|---|
| Gross outcome value | 60 × $2,000 | $120,000 |
| After 20% deadweight | $120,000 × 0.80 | $96,000 |
| After 25% attributed to others | $96,000 × 0.75 | $72,000 |
| After 10% displacement | $72,000 × 0.90 | $64,800 |
| SROI ratio | $64,800 ÷ $45,000 | 1.44:1 |
This example assumes a one-year horizon and no discounting within that period. It also assumes the adjustments are appropriate to this outcome and can be applied in this simplified sequence. A real analysis must explain those choices, avoid double counting and include material negative outcomes.
The arithmetic is straightforward. The hard questions are whether the outcome occurred, whether the valuation fits and whether the adjustment evidence supports the claim.
Use the calculator to explore a simplified single-outcome scenario. All starting numbers are illustrative. The tool applies the same annual outcome value to a fixed group, reduces later years by drop-off, and discounts each end-of-year value. It is a planning aid, not an assured SROI assessment.
For several outcomes or stakeholder groups, calculate each separately and check overlap before adding their values. Include relevant inputs consistently and document which negative outcomes are outside this simplified tool.
Change the assumptions that are both uncertain and influential. In the worked example, increasing deadweight from 20% to 40%, while holding other values constant, reduces adjusted value to $48,600 and the ratio to 1.08:1. At 50% deadweight it becomes $40,500, or 0.90:1.
Report a defensible range or a small set of scenarios rather than choosing only the most favorable result. The assumptions that move the conclusion most are candidates for better evidence collection. A range is useful only when its endpoints have a rationale.
Forecast SROI estimates future value using an expected pathway and assumptions. Evaluative SROI examines outcomes that have already occurred, while still requiring judgment about valuation and causation. Label the analysis clearly.
Do not blend expected future outcomes with observed outcomes without explaining which is which. Keep the forecast version so later evidence can be compared with the original assumptions.
For one program, keep the outcome definition, stakeholder group, valuation and reporting period together. For a portfolio, first check whether the units, time horizons, input definitions and valuation methods are comparable.
Do not simply average investee ratios. A weighted aggregate based on compatible value and input estimates may be appropriate, but it still needs checks for overlapping stakeholders, shared contributions and double counting. Sometimes the most honest portfolio report presents separate analyses with common definitions rather than a single ratio.
Quarterly partner submissions may include metrics, financial statements and narrative evidence. Connect them to the relevant investee and period, retain originals and flag inconsistent definitions for review. AI can assist that review; it cannot supply missing causal evidence.
A higher ratio is not automatically a better project. Comparing ratios across unrelated scopes or valuation methods can mislead. Read the analysis, not just the headline number.
Use these existing Academy guides for the practical next step. They are suggested companion readings; follow each guide’s course navigation for the full sequence.
Explore the Loop methodology for the ongoing cycle of collection, analysis and improvement.
Social return on investment.
There is no universal threshold that establishes quality. The scope, evidence, valuation, assumptions, distribution of effects and purpose of the decision matter.
Older guides describe seven. Social Value International added an eighth, Be responsive, in 2021; its current principles framework has eight.
No. SROI values social outcomes in relation to inputs. The estimated value is not necessarily cash income or a financial return to an investor.
Only with care. Differences in scope, stakeholders, valuations, time periods and methods can make ratios incomparable.
No. It demonstrates transparent arithmetic for a simplified scenario. A full analysis requires stakeholder involvement, evidence, materiality judgments and appropriate review.
