Todd M. Schneider
President, Chief Executive Officer, and Director at Cintas
Thank you, Jared. We are pleased with our start to fiscal year 2025. Our first quarter results reflect the strength and breadth of Cintas' value proposition for businesses of all types and stellar execution by our employee partners.
First quarter total revenue grew 6.8% to $2.5 billion, an all-time high for revenue in a quarter. First quarter revenue growth was negatively impacted by one less workday in the first quarter of fiscal 2025 compared to the first quarter of fiscal 2024. On a same-day work basis, first quarter revenue growth was 8.4%. The organic growth rate, which adjusts for the impacts of acquisitions, foreign currency exchange rate fluctuations, and the fact that there was one less workday in the quarter, was 8.0%. Each of Cintas' business divisions contributed to our success in the quarter.
As Mike will detail, our Rental Division was right where we liked them to be, and our First Aid and Safety and Fire Protection businesses each generated double-digit year-over-year growth, demonstrating the complementary nature of our platform and our long runway for future growth. The value of the products and services Cintas delivers continues to resonate with customers of all sizes and across industries.
We remain focused on the tremendous opportunity we have to serve 16 million businesses across North America. In the first quarter, we continue to experience strong demand for our services, not only from existing customers, but across our new business pipeline. Businesses across our four focused verticals of healthcare, hospitality, education, and state and local government continue to perform well.
Our top line results flow through to our bottom line. Gross margin for the first quarter increased 9.7% over the prior year to a record 50.1%. Operating income of 22.4% as a percent of revenue was also an all-time record, an increase of 12.1% over the prior year. Diluted EPS, which reflects the recent four-for-one stock split, grew a robust 18.3% to $1.10.
Our earnings growth continues to reflect our relentless focus on operational excellence in every aspect of our business, including strategic sourcing and supply chain initiatives that drive down our material cost, route and energy optimization with Smart Truck, and leveraging our SAP system to maximize the efficiency of our facilities.
Cash flow was very strong in the first quarter, with free cash flow increasing 62.4% over the prior year. Our cash generation enabled us to deploy capital across each of our capital allocation priorities. We continue to focus our strategic investments in our customers and our employee partners. This strategy is reflected in our capital allocation priorities that continue to position us to deliver long-term value for our shareholders.
In the first quarter, we continued to invest in our businesses through capital expenditure of $92.9 million and made acquisitions in each of our three route-based segments. Our technology investments are a significant area of reinvestment. We are making great strides to implement better technology-driven solutions to standardize our processes across our operations.
Hese investments have enabled us to provide more flexibility to our customers, including increased garment sharing and achieving more nimble and efficient product sourcing. Coupled with our ongoing partnerships with Verizon, Google, and SAP, we're able to make our employee partners' jobs easier and get the right products to our customers faster. We are seeing these efforts continue to improve customer experience and positively impact our margin profile.
In addition to making the investments in our business to fuel future growth, returning capital to Cintas shareholders through our dividend and share repurchase remains a key priority. Cintas increases quarterly dividend by 15.6% per share, which resulted in an aggregate quarterly cash dividend payment of $157.9 million on September 3rd. This marked the 41st consecutive year that we increased our dividend, meaning we have maintained this practice every year since going public. We also purchased $473.6 million worth of common stock during the quarter.
Before turning the call over to Mike to provide details of our first quarter results, I'll provide our updated financial expectations for our fiscal year, which reflect the momentum we carried through the first quarter and the exceptional dedication of our employee partners in helping our customers meet image, safety, cleanliness, and compliance needs.
We are increasing our financial guidance range for fiscal 2025. We are raising our annual revenue expectations from a range of $10.16 billion to $10.31 billion to a range of $10.22 billion to $10.32 billion, a total growth rate of 6.5% to 7.5%. We expect our organic growth rate to be in the range of 7.0% to 8.1%. We're also raising our annual diluted EPS expectations from a range of $4.06 to $4.19 to a range of $4.17 to $4.25, a growth rate of 10.0% to 12.1%. The future of Cintas remains bright, and I look forward to the year ahead.
With that, I'll turn the call over to Mike to discuss the details of our first quarter results.