West Pharmaceutical Services : Q3 2023 West Pharmaceutical Services Earnings Conference Call Presentation

Third-Quarter 2023

Cautionary Statement Under the Private Securities Litigation Reform Act of 1995

This presentation and any accompanying management commentary contain "forward-looking statements" as that term is defined in the Private Securities Litigation Reform Act of 1995. Such statements include, but are not limited to, statements about product development and operational performance. Each of these statements is based on preliminary information, and actual results could differ from any preliminary estimates. We caution investors that the risk factors listed under "Cautionary Statement" in our press releases, as well as those set forth under the caption "Risk Factors" in our most recent Annual Report on Form 10-K as filed with the Securities and Exchange Commission and as revised or supplemented by our quarterly reports on Form 10-Q, could cause our actual results to differ materially from those estimated or predicted in the forward-looking statements. You should evaluate any statement in light of these important factors. Except as required by law or regulation, we undertake no obligation to publicly update any forward-looking statements, whether as a result of new information, future events, or otherwise.

Non-U.S. GAAP Financial Measures

Certain financial measures included in these presentation materials, or which may be referred to in management's discussion of the Company's results and outlook, have not been calculated in accordance with U.S. generally accepted accounting principles ("U.S. GAAP"), and therefore are referred to as non- U.S. GAAP financial measures. Non-U.S. GAAP financial measures should not be considered in isolation or as an alternative to such measures determined in accordance with U.S. GAAP. Please refer to "Reconciliation of Non-U.S. GAAP Financial Measures" at the end of these materials for more information.

Safe Harbor Statement

WST Q3 2023 Earnings

Cautionary Statement Under the Private Securities Litigation Reform Act of 1995

This presentation and any accompanying management commentary contain "forward- looking statements" as that term is defined in the Private Securities Litigation Reform Act of 1995. Such statements include, but are not limited to, statements about product development, operational performance and expectations regarding future events. Each of these statements is based on preliminary information, and actual results could differ from any preliminary estimates.

We caution investors that the risk factors listed under our "Forward Looking Statements" in our press releases, as well as those set forth under the caption "Risk Factors" in our most recent Annual Report on Form 10-K as filed with the Securities and Exchange Commission and as revised or supplemented by our quarterly reports on Form 10-Q, could cause our actual results to differ materially from those estimated or predicted in the forward-looking statements. You should evaluate any statement in light of these important factors. Except as required by law or regulation, we undertake no obligation to publicly update any forward-looking statements, whether as a result of new information, future events, or otherwise.

Non-U.S. GAAP Financial Measures

Certain financial measures included in these presentation materials, or which may be referred to in management's discussion of the Company's results and outlook, have not been calculated in accordance with U.S. generally accepted accounting principles ("U.S. GAAP"), and therefore are referred to as non-U.S. GAAP financial measures. Non-U.S. GAAP financial measures should not be considered in isolation or as an alternative to such measures determined in accordance with U.S. GAAP. Please refer to "Reconciliation of Non-U.S. GAAP Financial Measures" at the end of these materials for more information.

Trademarks

Trademarks and registered trademarks used in this report are the property of West Pharmaceutical Services, Inc. or its subsidiaries, in the United States and other jurisdictions, unless noted otherwise.

Daikyo Crystal Zenith® and Daikyo CZ® are registered trademarks of Daikyo Seiko, Ltd. Daikyo Crystal Zenith technologies are licensed from Daikyo Seiko, Ltd.

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Financial Highlights

• Third quarter 2023 net sales of $747.4 million grew 8.8%; organic net sales increased 5.7%
• Third quarter 2023 reported-diluted EPS of $2.14 compared to $1.59 in the same period last year; adjusted-diluted EPS of $2.16 compared to $2.03 in the same period last year

Execute. Innovate. Grow.

A commitment and focus to deliver superior value to our customers and patients

Third-Quarter 2023 Summary Results

($ millions, except earnings-per-share (EPS) data)

1. "Adjusted Operating Profit," "Adjusted Operating Profit Margin" and "Adjusted-Diluted EPS" are Non-U.S. GAAP financial measures. See accompanying slides and the discussion under the heading "Non-U.S. GAAP Financial Measures" in today's press release for an explanation and reconciliation of these items.

Third-Quarter 2023 Organic

Net Sales Growth

Overall Organic Net Sales Increase: 5.7% (Q3 2023)

Proprietary Products Q3 2023 organic net sales increased 3.2% driven by growth in all three market units

Change in Consolidated Net Sales Third-Quarter 2022 to 2023

($ millions)

Gross Profit Update ($ millions)