Exhibit 99.1

Qualys Announces Fourth Quarter and Full Year 2018 Financial Results
2018 Revenue Growth of 21% Year-Over-Year
Q4 Revenue Growth of 18% Year-Over-Year
2018 GAAP EPS: $1.37; 2018Non-GAAP EPS: $1.75
Q4 GAAP EPS: $0.35; Q4Non-GAAP EPS: $0.51
Foster City, Calif., – Feb. 12, 2019 –Qualys, Inc. (NASDAQ:QLYS), a pioneer and leading provider of cloud-based security and compliance solutions, today announced financial results for the fourth quarter and full year ended December 31, 2018. For the quarter, the Company reported revenues of $74.2 million, net income under United States Generally Accepted Accounting Principles (“U.S. GAAP”) of $14.4 million,non-GAAP net income of $21.3 million, Adjusted EBITDA of $29.1 million, GAAP earnings per diluted share of $0.35, andnon-GAAP earnings per diluted share of $0.51. For the full year ended December 31, 2018, the Company reported revenues of $278.9 million, GAAP net income of $57.3 million,non-GAAP net income of $73.4 million, Adjusted EBITDA of $112.4 million, GAAP earnings per diluted share of $1.37 andnon-GAAP earnings per diluted share of $1.75.
“We achieved a solid fourth quarter, ending a strong year during which we grew revenues by 21%, produced record margins, saw new solutions contribute 20% of bookings and benefited from increased multi-product adoption. We delivered an impressive suite of new technology and application components to our Qualys Cloud Platform, including our innovative Global IT Asset Inventory application,” said Philippe Courtot, chairman and CEO of Qualys. “We believe that the scalability, accuracy, immediacy and breadth of our Qualys Cloud Platform continues to enable organizations across the globe to build security into their digital transformation initiatives as well as to consolidate their IT, security and compliance stacks.”
Fourth Quarter 2018 Financial Highlights
Revenues:Revenues for the fourth quarter of 2018 increased by 18% to $74.2 million compared to $62.9 million for the same quarter in 2017.
Gross Profit:GAAP gross profit for the fourth quarter of 2018 increased by 17% to $56.7 million compared to $48.5 million for the same quarter in 2017. GAAP gross margin percentage was 76% for the fourth quarter of 2018 compared to 77% for the same quarter in 2017.Non-GAAP gross profit for the fourth quarter of 2018 increased by 18% to $58.6 million compared to $49.5 million for the same quarter in 2017.Non-GAAP gross margin percentage was 79% for the fourth quarter of 2018 compared to 79% for the same quarter in 2017.
Operating Income: GAAP operating income for the fourth quarter of 2018 increased by 33% to $12.9 million compared to $9.7 million for the same quarter in 2017. As a percentage of revenues, GAAP operating income was 17% for the fourth quarter of 2018 compared to 15% for the same quarter in 2017.Non-GAAP operating income for the fourth quarter of 2018 increased by 22% to $22.8 million compared to $18.7 million for the same quarter in 2017. As a percentage of revenues,non-GAAP operating income was 31% for the fourth quarter of 2018 compared to 30% for the same quarter in 2017.