UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): July 1, 2016

STERIS plc

(Exact Name of Registrant as Specified in Charter)

Chancery House, 190 Waterside Road

Hamilton Industrial Park, Leicester LE5 1QZ

United Kingdom

(Address of Principal Executive Offices)

Registrant’s telephone number, including area code: +44 0 116 276 8636

Not Applicable

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Effective July 1, 2016, STERIS plc (“STERIS”) has sold its UK Linen Management Services business to STAR Mayan Limited for approximately £50 million. For fiscal year 2017, the UK Linen Management Services business was expected to generate approximately £40 million in revenue. As always, STERIS will continue to review its businesses for opportunities to optimize its portfolio of products and services.

STAR Mayan Limited is backed by the funds managed by STAR Capital, a European private equity fund manager that was founded in 2000, with the goal of acquiring and developing asset-based businesses either in partnership or independently. STAR is regulated by the Financial Conduct Authority. For more information, visit www.star-capital.com

Forward-Looking Statements

This Current Report on Form 8-K may contain statements concerning certain trends, expectations, forecasts, estimates, or other forward-looking information affecting or relating to STERIS or its industry, products or activities that are intended to qualify for the protections afforded “forward-looking statements” under the Private Securities Litigation Reform Act of 1995 and other laws and regulations. Forward-looking statements speak only as to the date specified in this Current Report and may be identified by the use of forward-looking terms such as “may,” “will,” “expects,” “believes,” “anticipates,” “plans,” “estimates,” “projects,” “targets,” “forecasts,” “outlook,” “impact,” “potential,” “confidence,” “improve,” “optimistic,” “deliver,” “comfortable,” “trend”, and “seeks,” or the negative of such terms or other variations on such terms or comparable terminology. Many important factors could cause actual results to differ materially from those in the forward-looking statements including, without limitation, disruption of production or supplies, changes in market conditions, political events, pending or future claims or litigation, competitive factors, technology advances, actions of regulatory agencies, and changes in laws, government regulations, labeling or product approvals or the application or interpretation thereof. Other risk factors are described herein and in STERIS’s other securities filings, including Item 1A of STERIS’s Annual Report on Form 10-K for the year ended March 31, 2016. Many of these important factors are outside of STERIS’s control. No assurances can be provided as to any result or the timing of any outcome regarding matters described in this Current Report or otherwise with respect to any regulatory action, administrative proceedings, government investigations, litigation, warning letters, cost reductions, business strategies, earnings or revenue trends or future financial results. References to products are summaries only and should not be considered the specific terms of the product clearance or literature. Unless legally required, STERIS does not undertake to update or revise any forward-looking statements even if events make clear that any projected results, express or implied, will not be realized. Other potential risks and uncertainties that could cause actual results to differ materially from those in the forward-looking statements include, without limitation, (a) STERIS’s ability to meet expectations regarding the accounting and tax treatments of the Combination (the “Combination”) with STERIS Corporation and Synergy Health plc (“Synergy”), (b) the possibility that the parties may be unable to achieve expected synergies and operating efficiencies in connection with the Combination within the expected time-frames or at all and to successfully integrate the operations of the companies, (c) the integration of the operations of the companies being more difficult, time-consuming or costly than expected, (d) operating costs, customer loss and business disruption (including, without limitation, difficulties in maintaining relationships with employees, customers, clients or suppliers) being greater than expected following the transaction, (e) the retention of certain key employees of Synergy being difficult, (f) changes in tax laws or interpretations that could increase our consolidated tax liabilities, including, changes in tax laws that would result in STERIS being treated as a domestic corporation for United States federal tax purposes, (g) the potential for increased pressure on pricing or costs that leads to erosion of profit margins, (h) the possibility that market demand will not develop for new technologies, products or applications or services, or business initiatives will take longer, cost more or produce lower benefits than anticipated, (i) the possibility that application of or compliance with laws, court rulings, certifications, regulations, regulatory actions, including without limitation those relating to FDA warning notices or letters, government investigations, the outcome of any pending FDA requests, inspections or submissions, or other requirements or standards may delay, limit or prevent new product introductions, affect the production and marketing of existing products or services or otherwise affect STERIS’s performance, results, prospects or value, (j) the potential of international unrest, economic downturn or effects of currencies, tax assessments, adjustments or anticipated rates, raw material costs or availability, benefit or retirement plan costs, or other regulatory compliance costs, (k) the possibility of reduced demand, or reductions in the rate of growth in demand, for STERIS’s products and services, (l) the possibility that anticipated growth, cost savings, new product acceptance, performance or approvals, or other results may not be achieved, or that transition, labor, competition, timing, execution, regulatory, governmental, or other issues or risks associated with STERIS’s businesses, industry or initiatives including, without limitation, those matters described in STERIS’s 10-K for the year ended March 31, 2016 and other securities filings, may adversely impact STERIS’s performance, results, prospects or value, (m) the impact on STERIS and its operations of the “Brexit,” (n) the possibility that anticipated financial results or benefits of recent acquisitions, including the Combination, or of STERIS’s restructuring efforts, or of the sale of the UK Linen Management Services Business will not be realized or will be other than anticipated and (o) the effects of the contractions in credit availability, as well as the ability of STERIS’s Customers and suppliers to adequately access the credit markets when needed.

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SIGNATURES

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 hereunto duly authorized.

Date: July 1, 2016

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