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What is a Sustainability-Linked Loan? A complete guide for borrowers and banks

A pillar guide to Sustainability-Linked Loans (SLLs): how the structure works, what the SLLP require, KPI and SPT selection, pricing mechanics, and how to run a credible SLL programme.

Redigo Carbon Editorial · 14 January 2026 · 9 min readLast reviewed 15 June 2026Based on Sustainability-Linked Loan Principles (LMA / APLMA / LSTA), GHG Protocol Corporate Standard
Sustainability-Linked LoansSustainable FinanceBanking

A Sustainability-Linked Loan (SLL) is a general-purpose credit facility whose economic terms — usually the interest margin — are contractually linked to the borrower's performance against predefined Sustainability Performance Targets (SPTs) measured through Key Performance Indicators (KPIs). Unlike a Green Loan, the proceeds are not restricted to green projects: any borrower with credible, ambitious sustainability targets can use an SLL to fund general corporate purposes.

SLLs are governed by the Sustainability-Linked Loan Principles (SLLP), jointly published by the LMA, APLMA and LSTA. They have grown from a niche instrument in 2017 to more than USD 500 billion of annual origination — now the largest category of sustainable lending globally.

How a Sustainability-Linked Loan works

An SLL has three moving parts:

  1. KPIs — the sustainability metrics the pricing is tied to. Typical examples: Scope 1+2 emissions (tCO₂e), energy intensity (kWh/unit), water intensity, waste recycling rate, safety metrics.
  2. SPTs — the ambitious, time-bound targets the borrower must meet against each KPI over the loan tenor.
  3. Margin adjustment — a step-down (usually 2.5–7.5 bps) if targets are met, a step-up if missed, and often a symmetric mechanism.

What the SLLP require

The Sustainability-Linked Loan Principles set five core components:

  • KPI selection — material, relevant to the borrower's business, quantifiable and comparable.
  • SPT calibration — ambitious beyond a business-as-usual trajectory, benchmarked against a science-based pathway or sector reference.
  • Loan characteristics — margin adjustment mechanism disclosed in the credit agreement.
  • Reporting — annual publication of KPI performance.
  • Verification — independent, external verification of KPI performance against each SPT at least annually.

Before signing, borrowers typically obtain a Second Party Opinion (SPO) confirming the framework's alignment with the SLLP.

Choosing the right KPIs

Weak KPI selection is the number one reason SLLs are criticised as greenwashing. Good practice:

  • Use absolute emission targets (tCO₂e) rather than intensity where feasible — intensity can improve while total emissions rise.
  • Include Scope 3 for sectors where it is >40% of the footprint.
  • Benchmark against SBTi-validated pathways.
  • Avoid KPIs the borrower already outperforms on a business-as-usual basis.

Verification and reporting

Under the SLLP, borrowers must obtain independent verification of KPI performance at least once a year. On the Redigo Carbon platform, verification is delivered by Audelya's network of independent reviewers; Redigo provides the technology that orchestrates measurement, evidence collection, review and reporting.

When an SLL is the right instrument

SLLs suit borrowers with material sustainability impacts and credible transition plans but without a discrete green project to finance. They are common in manufacturing, transport, food & beverage, real estate and services. For pure-play renewables developers or borrowers financing a specific green asset, a Green Loan is usually more appropriate.

Getting started

A realistic timeline from mandate to signing is 8–14 weeks: baseline measurement, KPI shortlist, SPT calibration against a science-based pathway, SPO, and integration into the credit agreement. Redigo Carbon compresses this timeline by automating measurement and orchestrating the SPO process end-to-end.

Frequently asked questions

What's the typical margin adjustment on an SLL?+

Market practice is 2.5–7.5 basis points of step-up or step-down per SPT, with two or three SPTs per facility. Some jurisdictions apply larger adjustments (10–25 bps) for sub-investment-grade borrowers.

Do SLLs require Scope 3 targets?+

Not strictly under the SLLP, but where Scope 3 is material (typically >40% of the footprint), reviewers and banks increasingly expect it. Excluding a material category weakens the SPO and undermines credibility.

What happens if targets are missed?+

The margin steps up per the credit agreement — this is the borrower's economic incentive. Persistent underperformance can also trigger reporting and remediation obligations, though not typically an event of default.

Can an SME access an SLL?+

Yes. Simplified SLL structures for SMEs — with a limited number of KPIs and lighter verification — are now standard at many EU banks. The Redigo Carbon platform is specifically designed to make SLL origination viable at SME scale.

This article follows Redigo Carbon's editorial standards: factual claims reference recognised frameworks — GHG Protocol, CSRD, ESRS, the Sustainability-Linked Loan Principles, the Green Loan Principles — and Redigo's opinions are labelled as such.

Sources & references

What this article is based on.

Redigo Carbon distinguishes between regulatory requirements, industry standards, best practice and Redigo's own recommendations. See our editorial standards for how we research, cite and update this content.

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