Exhibit 4.5



BT GROUP PLC

c/o ppA9F

BT Centre

81 Newgate Street

London

EC1A 7AJ

8 March 2017

Dear Jan,

The Board of BT Group plc (the Company) has agreed
your appointment as a non-executive director in advance of and in connection with your appointment as part-time Chairman of the Company and the Board. This letter sets out the terms of your appointment.

Appointment

Your appointment as a non-executive director will, unless otherwise agreed, commence on 1 June 2017. It will terminate automatically, without any entitlement to compensation or notice pay, on the date on which your appointment as
Chairman commences (which is expected to be 1 November 2017). During your appointment under this letter, either you or the Board can give the other at least one months written notice to terminate the appointment at any time. If for any
reason the Board does not give you that notice, you will not upon termination be entitled to any compensation in respect of your notice period or otherwise.

Your appointment is subject to the Companys Articles of Association. Nothing in this letter is intended to exclude or vary the terms of the Articles of
Association as they apply to you as a director of the Company.

In accordance with the relevant corporate governance provisions, you will be required to
stand for election at the Companys next Annual General Meeting and then, for so long as you remain a director, for re-election at the Companys Annual General Meeting each year.

If you are not re-elected by the shareholders at the Annual General Meeting, or your directorship is terminated under
the Companys Articles of Association, the Companies Act 2006 or in accordance with the Termination provision below, your appointment will terminate automatically, with immediate effect and



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BT GROUP PLC



without any compensation in respect of your notice period or otherwise.

Time commitment

You are expected to attend all meetings of the Board, the Annual General Meeting (in person) and any Board away days. If you cannot attend any meeting you
should advise the Secretary in advance. In addition, you will be expected to devote appropriate preparation time ahead of each Board meeting and to take part in at least one visit each year to one of BTs offices or other sites.

It is difficult to be precise about the amount of time you should expect to spend on this work, but we estimate that you should allow a minimum of 10 days for
the initial five-month period. You should allow a slightly higher commitment at the start of your appointment whilst you familiarise yourself with the BT group and go through our induction programme for new directors. You will also be expected to
devote additional time as is required to help ensure an orderly handover of responsibilities prior to you commencing your role as Chairman of the Company.

Additional time commitment may also be required if the Company is undergoing a period of particularly increased activity (such as a major acquisition or
capital transaction).

By accepting this appointment, you confirm that you are able to allocate sufficient time to meet what is expected of you in your
role as a non-executive director. You should obtain the agreement of the Chairman before accepting any additional commitments that might affect the time you are able to devote to your role as a non-executive director of the Company.

Role

Non-executive directors have the same general legal responsibilities to the Company as any other director. The
Boards principal focus is the strategy, development, growing shareholder value, oversight and control and governance of the group. In support of this it approves the groups strategic plans, annual and investment budgets and capital
expenditure. It sets the direction for the groups values, ethics and business policies and practices. It also has oversight of the groups operating and financial performance, risk management and internal controls, and compliance and
major public policy issues. Board members are expected to constructively challenge and help develop proposals



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BT GROUP PLC



on strategy. These responsibilities are set out in the formal statement of the Boards role, included in your directors briefing pack and are in accordance with the UK Corporate
Governance Code.

Fees and expenses

You will receive
fees for your services as a non-executive director of £72,000 a year. Your fees will be paid monthly in arrears subject to such deductions for income tax and social security contributions as the Company
may be required by law to deduct.

As a non-executive director, you will have no entitlement to any bonus and no
entitlement to participate in any employee share plan or pension scheme operated by the Company.

The Company will either pay or reimburse you for all
reasonable and properly documented travelling, hotel and other expenses incurred on the Companys business.

Any obligation of the Company or any
group companies under this letter and any other arrangement relating to remuneration from which you benefit or enter into after becoming a director of the Company shall be subject to and conditional on the approval by the Companys shareholders
in a general meeting of a policy on directors remuneration in accordance with the relevant legislation. If that approval is not obtained, you will not be entitled to compensation or damages in respect of any loss or damage suffered as a
result.

Independence

You are considered to be an
independent non-executive director and will be identified as such in the Companys annual report and other documentation. If circumstances change, and you believe that your independence may be in doubt,
you should discuss this with the Chairman or the Secretary as soon as practicable.

Outside interests

It is accepted and acknowledged that you have business interests other than those of the Company. You are required to disclose to the Board, via the Secretary,
any interests you have at the date of your appointment. Advice on



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BT GROUP PLC



notifiable interests is enclosed in your briefing pack. You will be asked to review the interests notified, on an annual basis. However, any new interests or potential conflicts of interests
which arise during your period of appointment should be notified to the Secretary as soon as they become apparent.

Confidentiality and share dealings

From the date of this letter, you must apply the highest standards of confidentiality and not disclose to any person, firm or company (whether during
the course of the appointment or at any time after its termination) any confidential information concerning the Company or any group companies with which you come into contact by virtue of your position as a
non-executive director of the Company (or, prior to 1 June 2017, by virtue of any activities that you undertake in preparation for taking up your role as a
non-executive director or Chairman of the Company).

For these purposes, confidential information shall include,
but not be limited to, information (whether or not recorded in documentary form, or stored on any magnetic or optical disk or memory) relating to the business, products, affairs and finances of the Company and/or any group companies, which is
treated as confidential to the Company and/or any group companies or which you are told or ought reasonably to know is confidential or which has been given to the Company and/or any group companies in confidence by customers, suppliers or other
persons, and any trade secrets including, without limitation, technical data and know-how relating to the business of the Company and/or any group companies or any of its or their business contacts.

Your attention is also drawn to the requirements under both legislation and regulation as to the handling and disclosure of inside information. You should
avoid making any statements that might breach these requirements without prior clearance from the Secretary.

You will be bound by the Companys
Articles of Association, any rules and regulations that may apply to the Company, including any rules issued by the United Kingdom Listing Authority, the Market Abuse Regulation and by the Companys share dealing code and such other
requirements as the Board may from time to time specify.

For a period of six years after the termination of your appointment, you may retain documents
and papers made available to you by the Company provided



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BT GROUP PLC



that (i) you comply strictly with the confidentiality obligations set out above, and (ii) you return to the Company all documents, papers and other property of or relating to the
business of the Company or any group company which are in your possession, custody or power by virtue of your position as a non-executive director of the Company at the end of that period, and you do not
retain copies (other than where the Company permits this). The Company is able to arrange the disposal of papers which you no longer require.

Induction and briefings

The Company has in place
arrangements to complement the briefing material you have already received about the BT group through an on-going programme to keep you informed about the Companys businesses, activities and
developments, the communications industry and the regulatory environment. This can include meetings with the Companys executive management, major shareholders and other stakeholders and the external auditors. We will also arrange a tailored
package of visits to business locations so you can see BT and its people at work.

Review

The performance of the Board and its committees is evaluated annually. If, in the interim, there are any matters which cause you concern about your role you
should discuss them with the Chairman or the Secretary as soon as is appropriate.

Individual training and development needs will be regularly reviewed
and agreed with each director as part of the Board evaluation process.

Insurance

You are covered by the Companys directors and officers liability insurance. We intend to continue to arrange this insurance cover. In the
event that we do not, run-off cover will be arranged for six years commencing from the date that cover under the latest insurance policy lapsed. The current limit in respect of any one claim or all claims in
aggregate during the period of the insurance policy is £200 million.



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BT GROUP PLC



Independent professional advice

The Company has a procedure for its directors, in furtherance of their duties, to take independent advice if necessary, at the Companys expense. If you
feel it necessary to seek such advice, please contact the Secretary first. A copy of the procedure is included in your briefing pack.

Termination

The Company may immediately terminate your appointment if you:



|a) | are in material breach of any of the terms of this letter;
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|b) | are guilty of gross misconduct and/or any serious or persistent negligence or misconduct in respect of your obligations under this letter;
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|c) | have engaged in any conduct which has or may have the effect of materially prejudicing the reputation of the Company or any other group company;
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|d) | terminate or seek to terminate your appointment as Chairman of the Company prior to its commencement; or
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|e) | fail or refuse to carry out the duties reasonably and properly required of you under this letter.
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Upon
termination of your appointment for any reason you will, at the Companys request, promptly resign in writing as a director of BT Group plc. The Secretary is irrevocably authorised by this letter to sign a letter of resignation on your behalf
if you fail to do so.

After your appointment is terminated, you will not represent yourself as being in any way concerned with or interested in the
business of the Company or any group companies.

Data protection

By signing this letter you consent to the Company holding and processing information about you (including sensitive personal data (as defined in the Data
Protection Act 1998)) for legal, personnel, administrative and management purposes. You consent to the Company making the information available to any of its group companies, those who provide products or services to the Company or any of its group
companies (such as advisers and payroll administrators), regulatory authorities, potential or future employers, governmental or quasi-governmental organisations and potential purchasers of the Company. You also



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consent to the transfer of the information to the Companys business contacts outside the European Economic Area in order to further its business interests.

Miscellaneous

You confirm that you will not by reason of
your appointment or your performance of any duties under this letter be in breach of any legal obligation binding on you.

This letter (and any document
referred to in it) constitutes the entire agreement between the parties and supersedes all other agreements (both oral and in writing) between you and the Company.

The terms of this letter are governed by English law and the parties submit to the exclusive jurisdiction of the English courts.

Acceptance

Please confirm your acceptance of these terms
by signing the attached copy of this letter as a deed and returning it. For convenience, this letter may be executed in counterparts. Once executed, the counterparts will constitute an original, and both counterparts together will constitute one
instrument.

Yours sincerely

/s/ Dan Fitz

Dan Fitz

Company Secretary



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BT GROUP PLC



|To: | Dan Fitz
|--- | --------

Company Secretary

I confirm acceptance of my appointment on the above terms.



|                                                  |  |                         |  | 
|------------------------------------------------- |  | ----------------------- |  | 
|SIGNED as a DEED and    )                         |  |                         |  | 
|DELIVERED by                                      |  | /s/ Jan du Plessis      |  | 
|                                                  |  |                        
|in the presence of:                               |  | /s/ Jacqueline Williams |  | 
|                                                  |  |                        
|Witnesss Signature1:                             |  |                         |  | 
|                                                  | 
|Witnesss Name (in capitals): JACQUELINE WILLIAMS |  |                        
|                                                  |  |                        
|Witnesss Address:                                |  |                         |  | 
|6 ST JAMESS SQUARE                               |  |                         |  | 
|LONDON SW1Y 4AD                                   |  |                         |  | 
|                                                  |  |                        
|Date: 8 March 2017                                |  |                         |  | 



|1 | A witness may be any person over the age of 18 who is not a member of your family.
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