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 of

the Securities Exchange Act of 1934

For the quarter ended September 30, 2021

Commission File Number 001—32945

WNS (HOLDINGS) LIMITED

(Translation of Registrant’s name into English)

Gate 4, Godrej & Boyce Complex

Pirojshanagar, Vikhroli (W)

Mumbai 400 079, India

+91-22-4095-2100

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover 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):  ☐

TABLE OF CONTENTS

Other Events

On October 28, 2021, WNS (Holdings) Limited issued an earnings release announcing its fiscal second quarter ended September 30, 2021 results and revised its guidance for fiscal 2022. A copy of the earnings release dated October 28, 2021 is attached hereto as Exhibit 99.1.

Exhibit

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: October 28, 2021

EXHIBIT INDEX

Exhibit 99.1

WNS Announces Fiscal 2022 Second Quarter Earnings,

Revises Full Year Guidance

NEW YORK, NY and MUMBAI, INDIA, October 28, 2021 — WNS (Holdings) Limited (WNS) (NYSE: WNS), a leading provider of global Business Process Management (BPM) solutions, today announced results for the fiscal 2022 second quarter ended September 30, 2021.

Reconciliations of the non-GAAP financial measures discussed below to our GAAP operating results are included at the end of this release. See also “About Non-GAAP Financial Measures.”

Revenue in the second quarter was $273.6 million, representing a 22.9% increase versus Q2 of last year and an 8.0% increase from the previous quarter. Revenue less repair payments* in the second quarter was $254.4 million, an increase of 18.7% year-over-year and a 7.7% increase sequentially. Excluding exchange rate impacts, constant currency revenue less repair payments* in the fiscal second quarter was up 16.2% versus Q2 of last year and 8.5% sequentially. Year-over-year, fiscal Q2 revenue improved as a result of new client additions, the expansion of existing relationships, increased travel volumes, and currency movements net of hedging. Sequentially, revenue improvement was driven by broad-based revenue growth across verticals and service offerings and increased travel volumes, which were partially offset by currency movements net of hedging.

Profit in the fiscal second quarter was $32.1 million, as compared to $29.2 million in Q2 of last year and $26.8 million in the previous quarter. Year-over-year, profit increased as a result of revenue growth, favorable currency movements net of hedging, and a lower effective tax rate. These benefits more than offset the impact of wage increases, the reinstatement of our corporate leave policy, increased facility-related and business continuity costs, and higher share-based compensation expense. Sequentially, Q2 profit increased as a result of revenue growth, reduced share-based compensation expense, and favorable currency movements net of hedging. These benefits were partially offset by wage increases and non-recurring Q1 profit items including interest income associated with a tax refund and a tax benefit on liquid mutual funds.

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Adjusted net income (ANI)* in Q2 was $43.1 million, as compared to $37.9 million in Q2 of last year and $39.0 million in the previous quarter. Explanations for the ANI* movements on a year-over-year and sequential basis are the same as described for GAAP profit above with the exception of amortization of intangible expenses, share-based compensation costs and associated tax impacts, which are excluded from ANI*.

From a balance sheet perspective, WNS ended Q2 with $332.2 million in cash and investments and $8.4 million of debt. In the second quarter, the company generated $47.3 million in cash from operations and incurred $7.1 million in capital expenditures. The company also made scheduled debt payments of $8.4 million. Second quarter days sales outstanding were 31 days, as compared to 34 days reported in Q2 of last year and 32 days in the previous quarter.

“Our fiscal second quarter financial results continue to highlight our differentiated positioning in the BPM marketplace and solid execution. The company delivered year-over-year revenue growth of 16.2% on a constant currency basis, posted adjusted operating margin of 21.8%, and expanded adjusted diluted earnings per share by 17.8%,” said Keshav Murugesh, WNS’s Chief Executive Officer. “We believe the BPM opportunity is both accelerating and expanding, as clients increasingly look for strategic digital transformation partners to help improve their competitive positioning.”

COVID-19

The COVID-19 pandemic is having a significant impact on the global economy, our clients’ businesses, and on WNS’s operations, financials, and visibility. Revenue has been pressured by lower client volumes, delays in new business ramps, client concessions, and facility lockdowns which impact service delivery. WNS is actively working to manage our clients’ changing requirements, adapt our service delivery models, ensure data security, and manage costs. In the fiscal second quarter, the company delivered more than 99% of our clients’ requirements. Going forward, impacts to our financial performance will be a function of how long the COVID-19 pandemic lasts on a global basis, and how long it takes our clients’ businesses to stabilize and recover.

Fiscal 2022 Guidance

WNS is updating guidance for the fiscal year ending March 31, 2022 as follows:

“The company has updated our forecast for fiscal 2022 based on current visibility levels and exchange rates,” said Sanjay Puria, WNS’s Chief Financial Officer. “Our guidance for the full year reflects growth in revenue less repair payments* of 13% to 17%, or 11% to 15% on a constant currency* basis. We currently have 98% visibility to the midpoint of the range, consistent with October guidance in previous years. For the year, we expect capital expenditures of up to $35 million.”

Conference Call

WNS will host a conference call on October 28, 2021 at 8:00 am (Eastern) to discuss the company’s quarterly results. To access the call in “listen-only” mode, please join live via the company’s investor relations website at ir.wns.com. For call participants, please use the following details: US dial-in +1-888-656-9018; international dial-in +1-503-343-6030; participant passcode 1565479. A replay will be available for one week following the call at +1-855-859-2056; international dial-in +1-404-537-3406; passcode 1565479, as well as on the WNS website, www.wns.com, beginning two hours after the end of the call.

About WNS

WNS (Holdings) Limited (NYSE: WNS) is a leading Business Process Management (BPM) company. WNS combines deep industry knowledge with technology, analytics and process expertise to co-create innovative, digitally led transformational solutions with over 375 clients across various industries. WNS delivers an entire spectrum of BPM solutions including industry-specific offerings, customer experience services, finance and accounting, human resources, procurement, and research and analytics to re-imagine the digital future of businesses. As of September 30, 2021, WNS had 49,511 professionals across 57 delivery centers worldwide including facilities in China, Costa Rica, India, the Philippines, Poland, Romania, South Africa, Spain, Sri Lanka, Turkey, the United Kingdom, and the United States. For more information, visit www.wns.com.

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Safe Harbor Statement

This release contains forward-looking statements, as defined in the safe harbor provisions of the US Private Securities Litigation Reform Act of 1995. These forward-looking statements are based on our current expectations and assumptions about our Company and our industry. Generally, these forward-looking statements may be identified by the use of terminology such as “anticipate,” “believe,” “estimate,” “expect,” “intend,” “will,” “seek,” “should” and similar expressions. These statements include, among other things, express or implied forward-looking statements relating to our expectations regarding the impact of the COVID-19 pandemic on our business, our cost structure, the discussions of our strategic initiatives and the expected resulting benefits, our growth opportunities, industry environment, expectations concerning our future financial performance and growth potential, including our fiscal 2022 guidance, future profitability, and expected foreign currency exchange rates. Forward-looking statements inherently involve risks and uncertainties that could cause actual results to differ materially from those expressed or implied by such statements. Such risks and uncertainties include but are not limited to worldwide economic and business conditions, our dependence on a limited number of clients in a limited number of industries; the impact of the COVID-19 pandemic on our and our clients’ business, financial condition, results of operations and cash flows; currency fluctuations; political or economic instability in the jurisdictions where we have operations; regulatory, legislative and judicial developments; increasing competition in the BPM industry; technological innovation; our liability arising from fraud or unauthorized disclosure of sensitive or confidential client and customer data; telecommunications or technology disruptions; our ability to attract and retain clients; negative public reaction in the US or the UK to offshore outsourcing; our ability to collect our receivables from, or bill our unbilled services to our clients; our ability to expand our business or effectively manage growth; our ability to hire and retain enough sufficiently trained employees to support our operations; the effects of our different pricing strategies or those of our competitors; our ability to successfully consummate, integrate and achieve accretive benefits from our strategic acquisitions, and to successfully grow our revenue and expand our service offerings and market share; and future regulatory actions and conditions in our operating areas. These and other factors are more fully discussed in our most recent annual report on Form 20-F and subsequent reports on Form 6-K filed with or furnished to the US Securities and Exchange Commission (SEC) which are available at www.sec.gov. We caution you not to place undue reliance on any forward-looking statements. Except as required by law, we do not undertake to update any forward-looking statements to reflect future events or circumstances.

References to “$” and “USD” refer to the United States dollars, the legal currency of the United States; references to “GBP” refer to the British pound, the legal currency of Britain; and references to “INR” refer to Indian Rupees, the legal currency of India. References to GAAP refers to International Financial Reporting Standards, as issued by the International Accounting Standards Board (IFRS).

CONTACT:

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WNS (HOLDINGS) LIMITED

CONDENSED CONSOLIDATED STATEMENTS OF INCOME

(Unaudited, amounts in millions, except share and per share data)

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WNS (HOLDINGS) LIMITED

CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL POSITION

(Unaudited, amounts in millions, except share and per share data)

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About Non-GAAP Financial Measures

The financial information in this release includes certain non-GAAP financial measures that we believe more accurately reflect our core operating performance. Reconciliations of these non-GAAP financial measures to our GAAP operating results are included below. A more detailed discussion of our GAAP results is contained in “Part I –Item 5. Operating and Financial Review and Prospects” in our annual report on Form 20-F filed with the SEC on May 14, 2021.

For financial statement reporting purposes, WNS has two reportable segments: WNS Global BPM and WNS Auto Claims BPM. Revenue less repair payments is a non-GAAP financial measure that is calculated as (a) revenue less (b) in the auto claims business, payments to repair centers for “fault” repair cases where WNS acts as the principal in its dealings with the third party repair centers and its clients. WNS believes that revenue less repair payments for “fault” repairs reflects more accurately the value addition of the business process management services that it directly provides to its clients. For more details, please see the discussion in “Part I – Item 5. Operating and Financial Review and Prospects – Overview” in our annual report on Form 20-F filed with the SEC on May 14, 2021.

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Constant currency revenue less repair payments is a non-GAAP financial measure. We present constant currency revenue less repair payments so that revenue less repair payments may be viewed without the impact of foreign currency exchange rate fluctuations, thereby facilitating period-to-period comparisons of business performance. Constant currency revenue less repair payments is presented by recalculating prior period’s revenue less repair payments denominated in currencies other than in US dollars using the foreign exchange rate used for the latest period, without taking into account the impact of hedging gains/losses. Our non-US dollar denominated revenues include, but are not limited to, revenues denominated in pound sterling, South African rand, Australian dollar and Euro.

WNS also presents or discusses (1) adjusted operating margin, which refers to adjusted operating profit (calculated as operating profit / (loss) excluding goodwill impairment, share-based expense and amortization of intangible assets) as a percentage of revenue less repair payments, (2) ANI, which is calculated as profit excluding goodwill impairment, share-based expense and amortization of intangible assets and including the tax effect thereon, (3) Adjusted net income margin, which refers to ANI as a percentage of revenue less repair payments, (4) net cash, which refers to cash and cash equivalents plus investments less long-term debt (including the current portion) and other non-GAAP financial measures included in this release as supplemental measures of its performance. WNS presents these non-GAAP financial measures because it believes they assist investors in comparing its performance across reporting periods on a consistent basis by excluding items that are non-recurring in nature and those it believes are not indicative of its core operating performance. In addition, it uses these non-GAAP financial measures (i) as a factor in evaluating management’s performance when determining incentive compensation and (ii) to evaluate the effectiveness of its business strategies. These non-GAAP financial measures are not meant to be considered in isolation or as a substitute for WNS’s financial results prepared in accordance with IFRS.

The company is not able to provide our forward-looking GAAP revenue, profit and earnings per ADS without unreasonable efforts for a number of reasons, including our inability to predict with a reasonable degree of certainty the payments to repair centers, our future share-based compensation expense under IFRS 2 (Share Based payments), amortization of intangibles associated with future acquisitions, goodwill impairment and currency fluctuations. As a result, any attempt to provide a reconciliation of the forward-looking GAAP financial measures (revenue, profit, earnings per ADS) to our forward-looking non-GAAP financial measures (revenue less repair payments*, ANI* and Adjusted diluted earnings* per ADS, respectively) would imply a degree of likelihood that we do not believe is reasonable.

Reconciliation of revenue (GAAP) to revenue less repair payments (non-GAAP) and constant currency revenue less repair payments (non-GAAP)

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Reconciliation of cost of revenue (GAAP to non-GAAP)

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Reconciliation of selling and marketing expenses (GAAP to non-GAAP)

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Reconciliation of operating profit (GAAP to non-GAAP)

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Reconciliation of basic earnings per ADS (GAAP to non-GAAP)

Reconciliation of diluted earnings per ADS (GAAP to non-GAAP)

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