How long should your sustainability report be?

Companies often debate the optimal length and level of detail to include in their sustainability reports. That’s understandable, considering the competing factors affecting today’s reporting landscape, from meeting internal expectations to meeting mandatory disclosure requirements. There’s a sense that both saying too much and saying too little carry risks.

The Harvard Law School Forum on Corporate Governance has tracked trends in sustainability reporting for the past five years. Between 2021 and 2024, they observed a steady increase in the average length of reports each year, from 70 pages in 2021 to 83 pages in 2024. While the group has yet to release an analysis of reports published in 2025, CRI’s own research shows that there's a bit more to the story.

Across 50 companies we surveyed, median report length decreased from 91 pages in 2023 to 86 pages in 2024. We found that about 50% of companies shortened their reports year over year, and of those, about 40% slashed page counts by 50% or more. On the other hand, more than half of the companies in our sample grew their reports or kept the length about the same.

This mixed bag aligns with our overall message to clients: the right length for your report is the one that’s right for your business. By shifting the focus away from page count and taking steps up front to define your story, you can take control of report content and produce a report that is compelling and useful without feeling like overkill. Here are a few ways to help find your sweet spot.

Define the report’s scope.

A materiality assessment can inform your report’s content by identifying the ESG topics that are most relevant to your stakeholders and applying a sustainability lens to business risk and opportunity. These assessments can also help internal stakeholders better understand decisions about what content stays or goes. For example, companies with complex environmental impacts may need to provide more detailed emissions data and disclosures. Revisiting your materiality matrix every couple of years will help ensure your organization stays relevant in a shifting ESG landscape.

If you’re not due for a full materiality update, doing some interim work like a peer benchmark or sensitivity assessment can help surface other relevant topics and ensure that your report adequately addresses the moment.

Identify your audience.

Perhaps your report needs to connect with policymakers who have questions about your business. Maybe you’re hoping it will help you stand out to prospects as an employer of choice. While you are likely trying to reach many audiences at once, zeroing in on your most important audiences will help you determine where to provide more context, and just as importantly, where to pull back.

It may also influence which reporting standards or frameworks you should include. For example, the Global Reporting Initiative takes a multi-stakeholder approach, while Sustainability Accounting Standards Board standards targets investors by focusing on sustainability risks and opportunities specific to each industry.

Engage your team.

Involve leaders and other key decision makers early to understand what a successful report looks like to them. In these conversations, seek to understand what accomplishments rise to the surface, as well as any internal politics that may influence what goes into the report. Insiders can also weigh in on topics that should be treated with sensitivity or omitted.

Use this input to guide information gathering, content creation and ultimately the report’s theme and structure. Being intentional about messaging and engaging the right people from the start will minimize rework and keep your report focused.

Get strategic — and creative.

With material issues, key audiences, and leadership input in hand, audit your previous report to map which information is key to your sustainability story and which might be better housed elsewhere. Keep in mind that your disclosure suite is not limited to an annual publication and could also include an online ESG Hub, executive summary, additional downloads, blog posts and more.

Then, consider which storytelling approaches are best suited to each key topic and communication channel. Depending on the audience you hope to reach, design elements like infographics, case studies and employee spotlights can humanize data and illustrate the real-world impacts of your sustainability strategy. While these types of content can increase page count, they tend to pack a greater communications punch and can often be leveraged for purposes beyond the report.

Fail to define your message, and you may end up with a report that is far too long for readers to absorb. Neglect to gather enough content, and your report may be too short to be meaningful. Approach the process with a clear content strategy, based on purposeful inputs from internal and external stakeholders, and you’ll be well on your way to creating a report whose length is just right.