CDW Corporation (together with its subsidiaries, the "Company," "CDW" or "we") is a Fortune 500 company and a leading provider of integrated information technology ("IT") solutions to small, medium and large business, government, education and healthcare customers in the United States ("US"), the United Kingdom ("UK") and Canada. Our broad array of offerings ranges from discrete hardware and software products to integrated IT solutions such as mobility, security, data center optimization, cloud computing, virtualization and collaboration. We are technology "agnostic," with a solutions portfolio including more than 100,000 products and services from more than 1,000 leading and emerging brands. Our solutions are delivered in physical, virtual and cloud-based environments through over 6,000 customer-facing coworkers including sellers, highly-skilled technology specialists and advanced service delivery engineers. We are a leading sales channel partner for many original equipment manufacturers ("OEMs"), software publishers and cloud providers (collectively, our "vendor partners"), whose products we sell or include in the solutions we offer. We provide our vendor partners with a cost-effective way to reach customers and deliver a consistent brand experience through our established end-market coverage, technical expertise and extensive customer access.
Total Net sales for the three months ended March 31, 2019 increased $352 million, or 9.7%, to $3,958 million, compared to $3,606 million for the three months ended March 31, 2018. Excluding the impact of foreign currency fluctuations, constant currency Net sales growth was 10.6%. There was one fewer selling day in the three months ended March 31, 2019 compared to the same period of 2018, and Net sales on an average daily sales basis increased 11.5%. See "Non-GAAP Financial Measure Reconciliations" below for additional detail regarding constant currency Net sales growth.
For the three months ended March 31, 2019, Net sales growth reflected growth across most major product categories, particularly client devices, software, servers and enterprise storage. Additionally, strong results from our international operations, including two months of Net sales from Scalar Decisions Inc. ("Scalar"), which was acquired on February 1, 2019, contributed to our Net sales growth.
Corporate segment Net sales for the three months ended March 31, 2019 increased $170 million, or 10.9%, compared to the three months ended March 31, 2018. On an average daily sales basis, Corporate segment Net sales increased 12.6%. Growth was primarily driven by client devices, software, networking and servers.