UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of March 2019

Commission File Number: 001-36515

Materialise NV

Technologielaan 15

3001 Leuven

Belgium

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F. Form 20-F   ☒    Form 40-F  ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  ☐

EXHIBIT INDEX

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: March 6, 2019

Exhibit 99.1

Materialise Reports Full Year and Fourth Quarter 2018 Results

LEUVEN, Belgium—(BUSINESS WIRE)—March 6, 2019 — Materialise NV (NASDAQ:MTLS), a leading provider of additive manufacturing and medical software and of sophisticated 3D printing services, today announced its financial results for the full year and fourth quarter ended December 31, 2018.

Highlights – Full Year and Fourth Quarter 2018

Full Year 2018:

Fourth Quarter 2018:

Executive Chairman Peter Leys commented, “2018 has been a good year for Materialise. Our annual revenues grew by 30% to 184,721 kEUR, our Adjusted EBITDA grew by 61% to 23,526 kEUR, and our deferred revenue from license and maintenance fees increased 3,883 kEUR to 22,606 kEUR, all at the higher end of the range we forecasted at the beginning of the year. In addition, cash flow from operating activities in 2018 was 28,321 kEUR compared to 9,951 kEUR in 2017, and, as a result of the capital we raised in 2018, our cash and cash equivalents at the end of 2018 totaled 115,506 kEUR compared to 43,175 kEUR at the end of last year. This financial strength positions us well to capture new growth opportunities going forward, even if the macro-economicconditions become less favorable.”

Fourth Quarter 2018 Results

Total revenue for the fourth quarter of 2018 increased 9.6% to 49,014 kEUR compared to 44,733 kEUR for the fourth quarter of 2017. Adjusted EBITDA increased to 6,052 kEUR from 5,806 kEUR. The Adjusted EBITDA margin (Adjusted EBITDA divided by total revenue) in the fourth quarter of 2018 was 12.3% compared to 13.0% in the fourth quarter of 2017.

Revenue from our Materialise Software segment decreased 4.1% to 10,044 kEUR for the fourth quarter of 2018 from 10,468 kEUR for the same quarter last year. Deferred revenue from license and maintenance fees within the segment increased by 965 kEUR compared to last year’s quarter. Segment EBITDA decreased to 2,969 kEUR from 4,619 kEUR while the segment EBITDA margin was 29.6% compared to 44.1% in the prior-year period.

Revenue from our Materialise Medical segment increased 27.4% to 15,081 kEUR for the fourth quarter of 2018 compared to 11,842 kEUR for the same period in 2017. Compared to the same quarter in 2017, revenues from medical devices and services grew 39.6%, and revenues from our medical software grew 6.9%. Segment EBITDA was 3,593 kEUR compared to 2,158 kEUR while the segment EBITDA margin increased to 23.8% from 18.2% in the fourth quarter of 2017.

Revenue from our Materialise Manufacturing segment increased 6.8% to 23,926 kEUR for the fourth quarter of 2018 from 22,394 kEUR for the fourth quarter of 2017. Segment EBITDA increased to 1,983 kEUR from 1,377 kEUR while the segment EBITDA margin increased to 8.3% from 6.1% for the same quarter in 2017.

Gross profit was 27,261 kEUR, or 55.6% of total revenue, for the fourth quarter of 2018 compared to 23,601 kEUR, or 52.8% of total revenue, for the fourth quarter of 2017.

Research and development (“R&D”), sales and marketing (“S&M”) and general and administrative (“G&A”) expenses increased, in the aggregate, 11.1% to 27,290 kEUR for the fourth quarter of 2018 from 24,553 kEUR for the fourth quarter of 2017.

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Net other operating income decreased by 1,135 kEUR to 810 kEUR compared to 1,945 kEUR for the fourth quarter of 2017. Net other operating income this quarter was impacted by higher provisions for doubtful trade receivables, which totaled 852 kEUR, and included the application of the new IFRS9 Financial Instruments accounting standard.

Operating result decreased to 781 kEUR from 993 kEUR for the same period in the prior year.

Net financial result was (420) kEUR compared to (356) kEUR for the prior-year period.

Net profit for the fourth quarter of 2018 was 525 kEUR, compared to net profit of 1,067 kEUR for the same period in 2017. The operating profit decreased by 212 kEUR and our share in the loss of a joint venture increased by 311 kEUR. Total comprehensive income for the fourth quarter of 2018, which includes exchange differences on translation of foreign operations, was 507 kEUR compared to 857 kEUR for the same period in 2017.

At December 31, 2018, we had cash and equivalents of 115,506 kEUR compared to 43,175 kEUR at December 31, 2017. Cash flow from operating activities for the full year 2018 was 28,321 kEUR compared to 9,951 kEUR in 2017.

Net shareholders’ equity at December 31, 2018 was 135,989 kEUR compared to 77,054 kEUR at December 31, 2017.

Full Year 2018 Results

Total revenues for the year ended December 31, 2018 increased 29.6% to 184,721 kEUR compared to 142,573 kEUR for the year ended December 31, 2017. Excluding the impact of our October 4, 2017 acquisition of ACTech, a full-service manufacturer of complex metal parts, revenues increased 6.6% to 141,329 kEUR. Adjusted EBITDA for the year ended December 31, 2018 was 23,526 kEUR, an increase of 61.0% compared to 14,610 kEUR for the year ended December 31, 2017. The Adjusted EBITDA margin increased to 12.7% from 10.2% last year. Excluding ACTech, Adjusted EBITDA was 14,097 kEUR for the year ended December 31, 2018 compared to 13,067 kEUR for the year ended December 31, 2017.

Revenues from our Materialise Software segment increased 4.5% to 37,374 kEUR for the year ended December 31, 2018 compared to 35,770 kEUR for the year ended December 31, 2017. The segment EBITDA margin was 30.9% in 2018 compared to 38.9% in 2017.

Revenues from our Materialise Medical segment grew by 22.0% for the year ended December 31, 2018 to 52,252 kEUR from 42,841 kEUR for the year ended December 31, 2017. Medical software growth was 9.1%, and revenues from medical devices and services increased 29.3%. The segment EBITDA margin increased to 19.6% from 10.3%, primarily as a result of the combination of revenue growth and limited increases in operating expenses.

Revenues from our Materialise Manufacturing segment increased 49.0% to 94,956 kEUR for the year ended December 31, 2018 from 63,712 kEUR for the year ended December 31, 2017. Excluding ACTech, revenues decreased 4.1% to 51,518 kEUR from 53,747 kEUR. The segment EBITDA margin increased from 7.0% in 2017 to 11.4% in 2018. Excluding ACTech, the segment EBITDA margin decreased to 2.7%.

Net profit improved from (2,117) kEUR for 2017 to a net profit of 3,027 kEUR for 2018.

2019 Guidance

Mr. Leys concluded, “The additive manufacturing market continues to evolve, as new applications gradually find their way to the market, and we intend to continue positioning Materialise to benefit from this promising growth market in the coming years. In 2019, Materialise will dedicate significant attention to the partnerships that we have entered into and to the strategic initiatives that we have launched over the previous years. In our Materialise Software segment, we intend to maintain our leadership position through innovation and strategic partnerships; in our Materialise Medical segment we will drive the next stage of innovation, including by launching initiatives in new growth areas; and in our Materialise Manufacturing segment we will increasingly focus on manufacturing of complex and unique parts.

“For fiscal 2019, we expect to report consolidated revenue between 196,000 kEUR – 204,000 kEUR and Adjusted EBITDA between 29,000 kEUR – 33,000 kEUR. We expect the amount of deferred revenue that Materialise generates from annual licenses and maintenance in 2019 to increase by an amount between 2,000 kEUR – 4,000 kEUR.”

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Adjusted EBITDA guidance for 2019 includes the positive impact, estimated at approximately 3,000 kEUR, of the application of the new IFRS16 Leases accounting standard, which requires leases to be recognized as an asset, and depreciated, over the lease term. As a result of the increased depreciation by approximately the same amount as the rental payments, our operating profit will not be impacted by this new standard.

Business Combinations—ACTech

Our audited financial statements for the year ended December 31, 2017 appearing in our Annual Report on Form 20-F, as filed with the U.S. Securities and Exchange Commission on April 30, 2018 (the “FY 2017 Form 20-F”), included a provisional accounting for the ACTech business combination. The fair value analysis with respect to the assets and liabilities acquired was not yet finalized as of the reporting date.

During September 2018, as previously reported in our Third Quarter 2018 Results release, and through October 4 2018, we completed the fair value analysis of the ACTech business combination, with corresponding adjustments to intangible assets, property, plant and equipment, inventories and contracts in progress, other current assets, investment grants and income taxes. The impact has been accounted for as retrospective adjustments to our consolidated statement of financial position as of December 31, 2017 and our consolidated income statement for the year ended December 31, 2017. Including an adjustment to the inventories valuation at ACTech, the total impact on the consolidated reserves for the year ended December 31, 2017 and our 2017 fourth quarter income statements amounted to (461) kEUR.

The adjustments are summarized as follows:

Consolidated statements of financial position

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Consolidated income statements

(*) Relates to an adjustment to the inventories valuation

Non-IFRS Measures

Materialise uses EBITDA and Adjusted EBITDA as supplemental financial measures of its financial performance. EBITDA is calculated as net profit plus income taxes, financial expenses (less financial income), shares of loss in a joint venture and depreciation and amortization. Adjusted EBITDA is determined by adding non-cash stock-based compensation expenses and acquisition-related expenses of business combinations to EBITDA. Management believes these non-IFRS measures to be important measures as they exclude the effects of items which primarily reflect the impact of long-term investment and financing decisions, rather than the performance of the company’s day-to-day operations. As compared to net profit, these measures are limited in that they do not reflect the periodic costs of certain capitalized tangible and intangible assets used in generating revenues in the company’s business, or the charges associated with impairments. Management evaluates such items through other financial measures such as capital expenditures and cash flow provided by operating activities. The company believes that these measurements are useful to measure a company’s ability to grow or as a valuation measurement. The company’s calculation of EBITDA and Adjusted EBITDA may not be comparable to similarly titled measures reported by other companies. EBITDA and Adjusted EBITDA should not be considered as alternatives to net profit or any other performance measure derived in accordance with IFRS. The company’s presentation of EBITDA and Adjusted EBITDA should not be construed to imply that its future results will be unaffected by unusual or non-recurring items.

Exchange Rate

This press release contains translations of certain euro amounts into U.S. dollars at specified rates solely for the convenience of readers. Unless otherwise noted, all translations from euros to U.S. dollars in this press release were made at a rate of EUR 1.00 to USD 1.145, the reference rate of the European Central Bank on December 31, 2018.

Conference Call and Webcast

Materialise will hold a conference call and simultaneous webcast to discuss its financial results for the fourth quarter of 2018 on the same day, Wednesday, March 6, 2019, at 8:30 a.m. ET/2:30 p.m. CET. Company participants on the call will include Wilfried Vancraen, Founder and Chief Executive Officer; Peter Leys, Executive Chairman; and Johan Albrecht, Chief Financial Officer. A question-and-answer session will follow management’s remarks.

To access the conference call, please dial 844-469-2530 (U.S.) or 765-507-2679 (international), passcode #8884671. The conference call will also be broadcast live over the Internet with an accompanying slide presentation, which can be accessed on the company’s website at http://investors.materialise.com.

A webcast of the conference call will be archived on the company’s website for one year.

About Materialise

Materialise incorporates more than 25 years of 3D printing experience into a range of software solutions and 3D printing services, which form the backbone of the 3D printing industry. Materialise’s open and flexible solutions enable players in a wide variety of industries, including healthcare, automotive, aerospace, art and design, and consumer goods, to build innovative 3D printing applications that aim to make the world a better and healthier place. Headquartered in Belgium, with branches worldwide, Materialise combines one of the largest groups of software developers in the industry with one of the largest 3D printing facilities in the world. For additional information, please visit: www.materialise.com.

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Cautionary Statement on Forward-Looking Statements

This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, regarding, among other things, our intentions, beliefs, assumptions, projections, outlook, analyses or current expectations, plans, objectives, strategies and prospects, both financial and business, including statements concerning, among other things, current estimates of fiscal 2019 revenues, deferred revenue from annual licenses and maintenance and Adjusted EBITDA, our expectations regarding fiscal 2019 sales, Adjusted EBITDA margin and investments, results of operations, cash needs, capital expenditures, expenses, financial condition, liquidity, prospects, growth and strategies (including our strategic priorities for 2019), and the trends and competition that may affect the markets, industry or us. Such statements are subject to known and unknown uncertainties and risks. When used in this press release, the words “estimate,” “expect,” “anticipate,” “project,” “plan,” “intend,” “believe,” “forecast,” “will,” “may,” “could,” “might,” “aim,” “should,” and variations of such words or similar expressions are intended to identify forward-looking statements. These forward-looking statements are based upon the expectations of management under current assumptions at the time of this press release. These expectations, beliefs and projections are expressed in good faith and the company believes there is a reasonable basis for them. However, the company cannot offer any assurance that our expectations, beliefs and projections will actually be achieved. By their nature, forward-looking statements involve risks and uncertainties because they relate to events, competitive dynamics and industry change, and depend on economic circumstances that may or may not occur in the future or may occur on longer or shorter timelines than anticipated. We caution you that forward-looking statements are not guarantees of future performance and involve known and unknown risks, uncertainties and other factors that are in some cases beyond our control. All of the forward-looking statements are subject to risks and uncertainties that may cause the company’s actual results to differ materially from our expectations, including risk factors described in the company’s annual report on Form 20-F filed with the U.S. Securities and Exchange Commission on April 30, 2018. There are a number of risks and uncertainties that could cause the company’s actual results to differ materially from the forward-looking statements contained in this press release.

The company is providing this information as of the date of this press release and does not undertake any obligation to update any forward-looking statements contained in this press release as a result of new information, future events or otherwise, unless it has obligations under the federal securities laws to update and disclose material developments related to previously disclosed information.

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Consolidated income statements (Unaudited)

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Consolidated statements of comprehensive income (Unaudited)

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Consolidated statements of financial position (Unaudited)

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Consolidated statements of cash flows (Unaudited)

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Reconciliation of Net Profit (Loss) to EBITDA and Adjusted EBITDA (Unaudited)

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Segment P&L (Unaudited)

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Reconciliation of Net Profit (Loss) to Segment EBITDA (Unaudited)

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