If you need money for one set green project, use a green loan. If you want general funding with loan pricing tied to ESG results, use an SLL.

I’d sum it up this way: the main difference is what the loan is built around. Green loans are tied to a named project and strict proceeds tracking. Sustainability-linked loans, or SLLs, are tied to company performance against KPIs and targets, with pricing that can move up or down. In the U.S., SLL volume reached about $52 billion in the first five months of 2021, up 292% from all of 2020, which shows how fast this part of lending grew.

Here’s the short version:

• Green loans fund a specific green project or asset.

• SLLs can be used for general corporate purposes.

• Green loans depend on eligible project categories and proceeds tracking.

• SLLs depend on KPIs, targets, reporting, and third-party checks.

• Green loans are more rigid on fund use.

• SLLs offer more freedom, but missed targets can mean a higher interest margin.

What matters most: project-based loan vs. performance-based loan.

Green Loans vs. Sustainability-Linked Loans: Key Differences at a Glance

Sustainable Finance: Green Loans and Sustainability-Linked Loans

Quick Comparison

If I were choosing between them, I’d ask one question first: Are you financing a project, or are you linking borrowing costs to company-wide ESG results? That answer usually points to the right structure.

What Is a Green Loan?

A green loan is used to finance or refinance eligible green projects, and the money must be used only for that purpose. [3]

Use of Proceeds and Eligible Project Categories

Under the Green Loan Principles (GLP), published jointly by the LMA, LSTA, and APLMA, eligible projects fall into a defined set of environmental categories [3]:

This list sets the boundary for what a green loan can fund. After that, the key issue becomes verification: lenders need a clear way to confirm that the proceeds are going where they should.

If a project stops meeting the green criteria, the loan can be declassified, and the borrower should no longer describe it as a green loan. [1]

Core Requirements Under Green Loan Principles

The GLP lays out four core requirements for borrowers: use of proceeds, project evaluation and selection, management of proceeds, and reporting. [3]

In practice, that means borrowers must use the funds only for eligible green projects and explain the environmental aims behind those projects, along with why each one qualifies. The proceeds should be tracked through a dedicated account or managed through another clear and traceable process. Reporting must give current information on how the funds were used, including a list of financed projects and their expected impact, using qualitative and, where possible, quantitative measures of environmental performance. Loan documents often include reporting undertakings and, in some cases, third-party audit requirements to check that the financed asset continues to meet green standards. [3]

That use-of-proceeds rule is the main point that separates green loans from sustainability-linked loans, where pricing changes based on performance instead.

What Is a Sustainability-Linked Loan?

A sustainability-linked loan (SLL) is a credit facility in which the financial terms - most often the interest margin - are tied to the borrower’s performance against agreed sustainability goals. Unlike a green loan, an SLL does not restrict how the proceeds are used. Instead, it links the loan’s economics to sustainability results. That distinction matters because it affects both pricing and documentation.

For borrowers, this can be a practical option. If a company wants financing connected to sustainability goals but does not have a single green project to fund, an SLL can fit that need.

KPIs, Sustainability Performance Targets, and Pricing Adjustments

An SLL stands on two building blocks: Key Performance Indicators (KPIs) and Sustainability Performance Targets (SPTs). KPIs need to matter to the borrower’s main business and sustainability plan. They are not just tracking tools; they directly affect pricing. Common examples include greenhouse gas emissions intensity, renewable electricity consumption, water usage efficiency, and gender diversity in management. [4][3]

After the KPIs are chosen, the borrower and lender set SPTs. These are specific, measurable targets meant to show material improvement beyond business as usual. The pricing then moves with performance. If the borrower hits the targets, the margin steps down. If the borrower misses them, the margin steps up.

The clearest dividing line between SLLs and green loans is use of proceeds. SLLs can support general corporate purposes, while green loans must finance a defined green project.

Pricing changes are usually small. For investment-grade borrowers, adjustments are often around 2.5 to 3 basis points. [5]

Core Requirements Under Sustainability-Linked Loan Principles

The Sustainability-Linked Loan Principles (SLLP), published jointly by the LMA, LSTA, and APLMA, set out five structural elements that every SLL must address:

Independent third-party assurance is strongly recommended and, in many cases, required. Self-certification should be used sparingly and mainly by borrowers with strong internal controls. [5] That safeguard helps reduce sustainability washing, which can happen when targets are too weak or when monitoring, measurement, or disclosure falls short. [5]

Loan documents may also include a rendez-vous clause, which allows KPIs and SPTs to be reset if the borrower’s strategy changes in a material way. [2]

Those structural differences set up the side-by-side comparison that follows.

Green Loans vs. Sustainability-Linked Loans: Side-by-Side Comparison

The difference between these two loan types comes into focus when you look at three things: how the money can be used, how progress is tracked, and what lenders need to see in the paperwork. In practice, that shows up most clearly in purpose, eligibility, reporting, and day-to-day flexibility.

Purpose, Eligibility, and Documentation

Green loan eligibility is tied to the project itself. The asset being financed must meet the Green Loan Principles, and the loan documents track where the funds go and what impact the project is meant to deliver.

Sustainability-linked loan, or SLL, eligibility works differently. It is tied to the borrower, not to one ring-fenced project. The borrower sets material KPIs and measurable SPTs, then lays out in the documentation how pricing shifts based on performance.

Put simply, green loans are project-based, while SLLs are borrower-based.

Reporting, Verification, and Flexibility

The reporting burden also splits in a pretty clear way. Green loans focus on allocation and impact. SLLs focus on KPI performance over time, and they also call for independent third-party verification of SPT results. If the borrower misses its SPTs, the usual outcome is a margin step-up rather than a default.[1][2]

Use Cases, Benefits, and How to Choose

Choose based on the asset, your funding needs, and how well you can track results. At this stage, the decision is less about labels and more about structure and readiness.

When a Green Loan Is the Better Fit

A green loan makes the most sense when you need to finance or refinance a specific, easy-to-define project - like renewable energy, an energy-efficiency retrofit, or a water infrastructure upgrade. The key point is simple: the financing must be linked to an eligible green project, and the proceeds need to be tracked in a clear, separate way.

This structure works well when the project qualifies under green lending criteria and you can ring-fence the funds and report on their use without much friction. Green loans can also help borrowers tap into capital set aside for green lending [3]. If your company does not yet have company-wide sustainability metrics in place, this is often the easier starting point. Why? Because the focus stays at the project level rather than on business-wide performance tracking.

If the financing is not tied to one defined project, a sustainability-linked loan is usually the better match.

When a Sustainability-Linked Loan Is the Better Fit

SLLs are better suited for broad corporate financing or day-to-day funding flexibility. If you need funding that can be used across the business - and you can support KPI-based reporting and verification - this structure tends to fit better.

That flexibility comes with more internal work. You need solid controls for KPI tracking, annual reporting, and verification. SLLs also often include a margin ratchet: if you hit the targets, the loan margin goes down; if you miss them, it can go up [2][3].

The fit becomes clearer in a side-by-side view:

Conclusion: Choosing the Right Instrument

The decision is practical, not ideological. Green loans fit eligible projects. SLLs fit flexible financing tied to company performance.

FAQs

Which loan is easier to qualify for?

Sustainability-linked loans are usually easier to qualify for than green loans.

Green loans have to fund specific eligible green projects, which can limit who can use them. Sustainability-linked loans, by contrast, can be used for general corporate purposes. That gives a broader mix of companies access to them, including smaller organizations.

Can one company use both a green loan and an SLL?

Yes. A company can use both green loans and sustainability-linked loans (SLLs).

In most cases, a single loan follows either the Green Loan Principles or the Sustainability-Linked Loan Principles because the two structures work in different ways. Even so, a company can still hold both types of financing at the same time.

What happens if sustainability targets are missed?

If an organization misses its sustainability performance targets, the loan agreement usually spells out what happens next. In many cases, the clearest outcome is financial: the borrower may face a higher interest rate.

That said, missing those targets usually does not trigger a default. The bigger issue is that the loan can lose its sustainability-linked label, which may lead to broader ripple effects for the organization.

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