Todd M. Schneider
Director, President & Chief Executive Officer at Cintas
Thank you, Jared.
We are pleased with our strong second quarter results, which reflect great execution by our employee partners, the comprehensive value proposition we provide to our customers in supporting their image, safety, cleanliness and compliance needs. Second quarter total revenue grew 7.8% to $2.56 billion, an all-time high for revenue in a quarter. The organic growth rate, which adjusts for the impacts of acquisitions and foreign currency exchange rate fluctuations was 7.1%. In the second quarter, we continued to experience strong demand for our services, reflecting the complementary nature of our platform and our unmatched product and service offerings for businesses of all types and sizes.
Virtually every business has a need Cintas is ready to meet, whether it's a front door that needs a mat, a bathroom to service, exit lighting, fire extinguishers and sprinkler systems, First Aid and safety needs or an Apparel solution. Cintas is continually deepening our value propositions, particularly within our four focused verticals, health care, hospitality, education and state and local government, which continued to perform well. Gross margin for the second quarter grew 11.8% over the prior year to 49.8%, just below our all time high we set in the first quarter. Operating income of 23.1% as a percent of revenue was an all time record, an increase of 18.4% over the prior year. Diluted EPS grew a robust 21.1% to $1.09. Our strong earnings growth reflects our operational excellence via sourcing and supply chain initiatives, route and energy optimization and technology enabled efficiency in our facilities.
Cash flow this year continues to be very strong with free cash flow for the first six months increasing 34.9% over the prior year. We continued to deploy capital across each of our capital allocation priorities, starting with investing back into our businesses. This strong cash flow generation allows us to focus on making strategic investments in our customers and our employee partners, which positions us to deliver long-term value for our shareholders. Our technology investments remain a significant area of reinvestment. We continue to leverage our SAP system to standardize our processes across our operations.
Combined with our focus on operational excellence, we are improving the way our employees work in getting the right products to our customers faster, all of which improves the customer experience and positively impacts our margin profile. At the same time of investing in our customers and employee partners and making strategic acquisitions, returning capital to Cintas' shareholders remains a key priority. Cintas paid a quarterly cash dividend of $0.39 per share last week. And looking ahead, we will continue our opportunistic approach with share buybacks.
Before turning the call over to Mike to provide details of our second quarter results, I'll provide our updated financial expectations for our fiscal year, which reflect our strong momentum and confidence in our outlook. We are updating our annual revenue expectations from a range of $10.22 billion to $10.32 billion to a range of $10.255 billion to $10.32 billion, a total growth rate of 6.9% to 7.5%. We expect our organic growth rate to be in the range of 7.0% to 7.7%. We are also updating our annual diluted EPS expectations from a range of $4.17 to $4.25 to a range of $4.28 to $4.34, a growth rate of 12.9% to 14.5%.
Cintas' differentiated culture, superior products and services and industry best talent position us to deliver meaningful value creation in fiscal 2025 and beyond. We remain focused on delivering outstanding customer experiences and making appropriate investments in the business to sustain our growth. I thank all Cintas' employee partners whose outstanding work and dedication to our customers remains the key to our success.
With that, I'll turn it over to Mike to discuss the details of our second quarter results.