EX-99.1

Supplemental Investor Information

July 13, 2015

Exhibit 99.1

Forward Looking Statements

This document contains forward-looking statements that involve a number of risks and uncertainties. Statements that are not

historical facts, including statements regarding expectations, hopes, intentions or strategies regarding the future are forward-

looking statements. Forward-looking statements are based on Willis or Towers Watson management’s beliefs, as well as

assumptions made by, and information currently available to, them. Because such statements are based on expectations as to

future financial and operating results and are not statements of fact, actual results may differ materially from those projected.

Willis and Towers Watson undertake no obligation to update any forward-looking statements, whether as a result of new

information, future events or otherwise. The risks and uncertainties which forward-looking statements are subject to include, but

are not limited to: the ability to consummate the proposed transaction; the ability to obtain requisite regulatory and shareholder

approvals and the satisfaction of other conditions to the consummation of the proposed transaction on the proposed terms and

schedule; the ability of Willis and Towers Watson to successfully integrate their respective operations and employees and realize

synergies and cost savings at the times, and to the extent, anticipated; the potential impact of the announcement or

consummation of the proposed transaction on relationships, including with employees, suppliers, customers and competitors;

changes in general economic, business and political conditions, including changes in the financial markets; significant competition

that Willis and Towers Watson face; compliance with extensive government regulation; the combined company’s ability to make

acquisitions and its ability to integrate or manage such acquired businesses; and other risks detailed in the “Statement Regarding

Forward-Looking Information,” “Risk Factors” and other sections of Willis’s and Towers Watson’s Form 10-K and other filings with

the Securities and Exchange Commission.

Transaction Overview

Transaction

Structure

Merger of equals

Approximately $18

billion transaction value

Pro forma

ownership: 50.1% Willis shareholders and 49.9% Towers Watson shareholders, on a

fully diluted basis

Combined company will be named Willis Towers Watson

Shareholder

Consideration

Towers

Watson

shareholders

receive

2.6490

Willis

for

each

Towers

Watson

Towers Watson shareholders to receive one-time $4.87 per share cash dividend pre-closing

Subject to Willis shareholder approval, Willis will implement at the time of the merger a 2.6490

for one reverse stock split, so that one Willis share will be converted into 0.3775 shares of the

combined company

(1)

If the reverse split is approved, Towers Watson shareholders to receive 1 share of the combined

company for each Towers Watson share

Governance

James McCann to be Chairman

John

Haley

to be CEO

Dominic

Casserley

to be President and Deputy CEO

Roger

Millay

to be CFO

12 person Board; 6 Willis directors and 6 Towers Watson directors

Domicile/

Locations

Maintain Irish domicile and significant presence in major markets globally

Closing

Conditions

Closing expected by December 31, 2015

Subject to customary closing conditions, including Willis and

Towers Watson shareholder

approvals and regulatory approvals

(1) Merger is not conditioned on approval of the reverse stock split.

Highly Complementary Combination Delivers Compelling Value

COMBINATION LEVERAGES UNIQUE STRENGTHS OF BOTH COMPANIES TO ADVANCE

STRATEGIC PRIORITIES

Merger of equals reflects complementary assets and facilitates value-creating integration

MANAGEMENT TEAM BRINGS SUCCESSFUL MERGER OF EQUALS INTEGRATION TRACK

RECORD

Proven ability to create shareholder value

GENERATES ESTIMATED AGGREGATE $4.65 BILLION IN INCREMENTAL VALUE FOR

SHAREHOLDERS OF BOTH COMPANIES

CREATES LEADING GLOBAL ADVISORY, BROKING AND SOLUTIONS FIRM WITH PROVEN

BUSINESS MODEL

Continues current expectation for top line growth and margins and greatly enhances anticipated EPS growth

Estimated $4.65 Billion in Total Incremental Value

~$1.5

billion

value

from

revenue

synergies

(3)

~$1.65

billion

value

from

cost

synergies

(5)

$100-125 million of run-rate cost synergies

Incremental to Operational Improvement Program

~$1.5 billion in value from tax savings (2016) on

existing Towers Watson earnings

(4)

$18.15

$1.65

$1.5

$22.8

(1)

($bn)

Estimated Value to Shareholders

$11.5 billion (including $337

million special dividend)

(2)

$11.3 billion

(1) $22.8 billion is pre-dividend. $22.5 billion is ex-dividend. The combined market capitalization of $18.1 billion is as of June 29, 2015.

(2) Calculated as 49.9% pro forma ownership (ex-dividend) plus the special one-time dividend of $337mm.

(3) ~$525mm of run-rate revenue synergies capitalized based on Towers Watson’s average P/E of ~20x and Willis’ average P/E of ~17x (6-month average NTM P/E preceding announcement).

(4) Illustratively represents ~$75 million of savings per annum at Towers Watson capitalized at Towers Watson calendar year 2016E cash P/E multiple of 20.3x as of June 29, 2015.

(5) $125 million run-rate synergies capitalized based on Towers Watson’s average P/E of ~20x and Willis’ average P/E of ~17x (6-month average NTM P/E preceding announcement).

Estimated Annual Revenue Opportunity by Year 3: $375-$675 Million

$100-$400 million

~$200 million

~$75 million

MIDDLE MARKET EXCHANGE

Segment includes 40+ million employees and has a higher adoption rate

than large-market segment

Willis’ 20,000 mid-market U.S. relationships provide access to nearly half of

the addressable market

LARGE MARKET P&C BROKERAGE

Willis has a ~3.5% share of $10+ billion U.S. large P&C corporate market

Towers Watson has existing relationships with 80% of the companies in the

market, best-in-class insurance analytics and a strong brand

GLOBAL HEALTH AND GROUP BENEFITS

Towers Watson is globalizing market leading Liazon

platform

Willis provides expanded distribution network of more than 120 countries

Important Information

Responsibility Statement

WILLIS

TOWERS WATSON

200 Liberty Street, 7th Floor

New York,

10281-1003

901 N. Glebe Road

Arlington, VA 22203

Attention: Investor Relations

212-915-8084

703-258-8000

investor.relations@willis.com

investor.relations@towerswatson.com

The directors of Willis accept responsibility for the information contained in this document other than that relating to Towers Watson, the Towers Watson Group and the directors of Towers

Watson and members of their immediate families, related trusts and persons connected with them. To the best of the knowledge and belief of the directors of Willis (who have taken all

reasonable care to ensure that such is the case) the information contained in this document for which they accept responsibility is in accordance with the facts and does not omit anything likely to

affect the import of such information.

The directors of Towers Watson accept responsibility for the information contained in this document relating to Towers Watson, the Towers Watson Group and the directors of Towers Watson and

members of their immediate families, related trusts and persons connected with them. To the best of the knowledge and belief of the directors of Towers Watson (who have taken all reasonable

care to ensure that such is the case) the information contained in this document for which they accept responsibility is in accordance with the facts and does not omit anything likely to affect the

import of such information.

Important Information About the Transaction and Where to Find It

Willis and Towers Watson, and their respective directors and executive officers, may be deemed to be participants in the solicitation of proxies in respect of the transactions contemplated by the

merger agreement. Information regarding the directors and executive officers of Willis, and their direct or indirect interests in the transaction, by security holdings or otherwise, is contained in

Willis’s Form 10-K for the year ended December 31, 2014 and its proxy statement filed on April 17, 2015, which are filed with the SEC. Information regarding Towers Watson’s directors and

executive officers, and their direct or indirect interests in the transaction, by security holdings or otherwise, is contained in Towers Watson’s Form 10-K for the year ended June 30, 2014 and its

proxy statement filed on October 3, 2014, which are filed with the SEC. A more complete description will be available in the Registration Statement and the Joint Proxy Statement/Prospectus.

Participants in the Solicitation

This document shall not constitute an offer to sell or the solicitation of an offer to sell or the solicitation of an offer to buy any securities, nor shall there be any sale of securities in any jurisdiction in

which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offer of securities shall be made except by means of

a prospectus meeting the requirements of Section 10 of the Securities Act of 1933, as amended.

Willis plans to file with the SEC a Registration Statement on Form S-4 in connection with the transaction. Willis and Towers Watson plan to file with the SEC and mail to their respective shareholders

a Joint Proxy Statement/Prospectus in connection with the transaction. The Registration Statement and the Joint Proxy Statement/Prospectus will contain important information about Willis, Towers

Watson, the transaction and related matters. Investors and security holders are urged to read the Registration Statement, the Joint Proxy Statement/Prospectus and other related documents

carefully when they are available.

Investors and security holders will be able to obtain free copies of the Registration Statement, the Joint Proxy Statement/Prospectus and other related documents filed with the SEC by Willis and

Towers Watson through the web site maintained by the SEC at www.sec.gov or by contacting the investor relations department of Willis or Towers Watson at the following: