Director/PDMR Shareholding

1.

Details of PDMR/person closely associated with them ('PCA')

a)

Name

Ms E Walmsley

b)

Position/status

Chief Executive Officer

c)

Initial notification/

amendment

Initial notification

2.

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

GlaxoSmithKline plc

b)

LEI

5493000HZTVUYLO1D793

3.

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted

a)

Description of the financial  instrument

Ordinary shares of 25 pence each ('Ordinary Shares')

ISIN: GB0009252882

b)

Nature of the transaction

Acquisition of Ordinary Shares following the re-investment of dividends paid to shareholders on 12 April 2018 on Ordinary Shares held in the Company's Deferred Annual Bonus Plan.

c)

Price(s) and volume(s)

d)

Aggregated information

Aggregated volume Price

1,986.129

£14.296

e)

Date of the transaction

2018-04-12

f)

Place of the transaction

London Stock Exchange (XLON)

1.

Details of PDMR/person closely associated with them ('PCA')

a)

Name

Mr R G Connor

b)

Position/status

President, Global Manufacturing & Supply

c)

Initial notification/

amendment

Initial notification

2.

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

GlaxoSmithKline plc

b)

LEI

5493000HZTVUYLO1D793

3.

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted

a)

Description of the financial  instrument

Ordinary shares of 25 pence each ('Ordinary Shares')

ISIN: GB0009252882

b)

Nature of the transaction

Acquisition of Ordinary Shares following the re-investment of dividends paid to shareholders on 12 April 2018 on Ordinary Shares held in the Company's Deferred Annual Bonus Plan.

c)

Price(s) and volume(s)

d)

Aggregated information

Aggregated volume Price

651.559

£14.296

e)

Date of the transaction

2018-04-12

f)

Place of the transaction

London Stock Exchange (XLON)

1.

Details of PDMR/person closely associated with them ('PCA')

a)

Name

Mr L Debruyne

b)

Position/status

President, Global Vaccines

c)

Initial notification/

amendment

Initial notification

2.

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

GlaxoSmithKline plc

b)

LEI

5493000HZTVUYLO1D793

3.

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted

a)

Description of the financial  instrument

Ordinary shares of 25 pence each ('Ordinary Shares')

ISIN: GB0009252882

b)

Nature of the transaction

Acquisition of Ordinary Shares following the re-investment of dividends paid to shareholders on 12 April 2018 on Ordinary Shares held in the Company's Deferred Annual Bonus Plan.

c)

Price(s) and volume(s)

d)

Aggregated information

Aggregated volume Price

774.475

£14.296

e)

Date of the transaction

2018-04-12

f)

Place of the transaction

London Stock Exchange (XLON)

1.

Details of PDMR/person closely associated with them ('PCA')

a)

Name

Mr S Dingemans

b)

Position/status

Chief Financial Officer

c)

Initial notification/

amendment

Initial notification

2.

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

GlaxoSmithKline plc

b)

LEI

5493000HZTVUYLO1D793

3.

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted

a)

Description of the financial  instrument

Ordinary shares of 25 pence each ('Ordinary Shares')

ISIN: GB0009252882

b)

Nature of the transaction

Acquisition of Ordinary Shares following the re-investment of dividends paid to shareholders on 12 April 2018 on Ordinary Shares held in the Company's Deferred Annual Bonus Plan.

c)

Price(s) and volume(s)

d)

Aggregated information

Aggregated volume Price

1,819.049

£14.296

e)

Date of the transaction

2018-04-12

f)

Place of the transaction

London Stock Exchange (XLON)

1.

Details of PDMR/person closely associated with them ('PCA')

a)

Name

Mr N Hirons

b)

Position/status

SVP, Global Ethics & Compliance

c)

Initial notification/

amendment

Initial notification

2.

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

GlaxoSmithKline plc

b)

LEI

5493000HZTVUYLO1D793

3.

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted

a)

Description of the financial  instrument

Ordinary shares of 25 pence each ('Ordinary Shares')

ISIN: GB0009252882

b)

Nature of the transaction

Acquisition of Ordinary Shares following the re-investment of dividends paid to shareholders on 12 April 2018 on Ordinary Shares held in the Company's Deferred Annual Bonus Plan.

c)

Price(s) and volume(s)

d)

Aggregated information

Aggregated volume Price

526.263

£14.296

e)

Date of the transaction

2018-04-12

f)

Place of the transaction

London Stock Exchange (XLON)

1.

Details of PDMR/person closely associated with them ('PCA')

a)

Name

Mr L Miels

b)

Position/status

President, Global Pharmaceuticals

c)

Initial notification/

amendment

Initial notification

2.

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

GlaxoSmithKline plc

b)

LEI

5493000HZTVUYLO1D793

3.

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted

a)

Description of the financial  instrument

Ordinary shares of 25 pence each ('Ordinary Shares')

ISIN: GB0009252882

b)

Nature of the transaction

Acquisition of Ordinary Shares following the re-investment of dividends paid to shareholders on 12 April 2018 on Ordinary Shares held in the Company's Deferred Annual Bonus Plan.

c)

Price(s) and volume(s)

d)

Aggregated information

Aggregated volume Price

n/a (single transaction)

e)

Date of the transaction

2018-04-12

f)

Place of the transaction

London Stock Exchange (XLON)

1.

Details of PDMR/person closely associated with them ('PCA')

a)

Name

Mr B McNamara

b)

Position/status

CEO, GSK Consumer Healthcare

c)

Initial notification/

amendment

Initial notification

2.

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

GlaxoSmithKline plc

b)

LEI

5493000HZTVUYLO1D793

3.

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted

a)

Description of the financial  instrument

American Depositary Shares ('ADSs')

ISIN: US37733W1053

b)

Nature of the transaction

Acquisition of ADSs following the re-investment of dividends paid to shareholders on 12 April 2018 on ADSs held in the Company's Deferred Annual Bonus Plan.

c)

Price(s) and volume(s)

d)

Aggregated information

Aggregated volume Price

203.235

$40.62

e)

Date of the transaction

2018-04-12

f)

Place of the transaction

New York Stock Exchange (XNYS)

1.

Details of PDMR/person closely associated with them ('PCA')

a)

Name

Mr D S Redfern

b)

Position/status

Chief Strategy Officer

c)

Initial notification/

amendment

Initial notification

2.

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

GlaxoSmithKline plc

b)

LEI

5493000HZTVUYLO1D793

3.

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted

a)

Description of the financial  instrument

Ordinary shares of 25 pence each ('Ordinary Shares')

ISIN: GB0009252882

b)

Nature of the transaction

Acquisition of Ordinary Shares following the re-investment of dividends paid to shareholders on 12 April 2018 on Ordinary Shares held in the Company's Deferred Annual Bonus Plan.

c)

Price(s) and volume(s)

d)

Aggregated information

Aggregated volume Price

728.103

£14.296

e)

Date of the transaction

2018-04-12

f)

Place of the transaction

London Stock Exchange (XLON)

1.

Details of PDMR/person closely associated with them ('PCA')

a)

Name

Ms C Thomas

b)

Position/status

SVP, Human Resources

c)

Initial notification/

amendment

Initial notification

2.

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

GlaxoSmithKline plc

b)

LEI

5493000HZTVUYLO1D793

3.

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted

a)

Description of the financial  instrument

Ordinary shares of 25 pence each ('Ordinary Shares')

ISIN: GB0009252882

b)

Nature of the transaction

Acquisition of Ordinary Shares following the re-investment of dividends paid to shareholders on 12 April 2018 on Ordinary Shares held in the Company's Deferred Annual Bonus Plan.

c)

Price(s) and volume(s)

d)

Aggregated information

Aggregated volume Price

1,001.414

£14.296

e)

Date of the transaction

2018-04-12

f)

Place of the transaction

London Stock Exchange (XLON)

1.

Details of PDMR/person closely associated with them ('PCA')

a)

Name

Ms K Terrell

b)

Position/status

Chief Digital & Technology Officer

c)

Initial notification/

amendment

Initial notification

2.

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

GlaxoSmithKline plc

b)

LEI

5493000HZTVUYLO1D793

3.

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted

a)

Description of the financial  instrument

American Depositary Shares ('ADSs')

ISIN: US37733W1053

b)

Nature of the transaction

Acquisition of ADSs following the re-investment of dividends paid to shareholders on 12 April 2018 on ADSs held in the Company's Deferred Annual Bonus Plan.

c)

Price(s) and volume(s)

d)

Aggregated information

Aggregated volume Price

n/a (single transaction)

e)

Date of the transaction

2018-04-12

f)

Place of the transaction

New York Stock Exchange (XNYS)

1.

Details of PDMR/person closely associated with them ('PCA')

a)

Name

Mr P C Thomson

b)

Position/status

President, Global Affairs

c)

Initial notification/

amendment

Initial notification

2.

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

GlaxoSmithKline plc

b)

LEI

5493000HZTVUYLO1D793

3.

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted

a)

Description of the financial  instrument

Ordinary shares of 25 pence each ('Ordinary Shares')

ISIN: GB0009252882

b)

Nature of the transaction

Acquisition of Ordinary Shares following the re-investment of dividends paid to shareholders on 12 April 2018 on Ordinary Shares held in the Company's Deferred Annual Bonus Plan.

c)

Price(s) and volume(s)

d)

Aggregated information

Aggregated volume Price

376.366

£14.296

e)

Date of the transaction

2018-04-12

f)

Place of the transaction

London Stock Exchange (XLON)

1.

Details of PDMR/person closely associated with them ('PCA')

a)

Name

Mr D E Troy

b)

Position/status

SVP & General Counsel

c)

Initial notification/

amendment

Initial notification

2.

Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor

a)

Name

GlaxoSmithKline plc

b)

LEI

5493000HZTVUYLO1D793

3.

Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transaction(s) has been conducted

a)

Description of the financial  instrument

American Depositary Shares ('ADSs')

ISIN: US37733W1053

b)

Nature of the transaction

Acquisition of ADSs following the re-investment of dividends paid to shareholders on 12 April 2018 on ADSs held in the Company's Deferred Annual Bonus Plan.

c)

Price(s) and volume(s)

d)

Aggregated information

Aggregated volume Price

597.742

$40.62

e)

Date of the transaction

2018-04-12

f)

Place of the transaction

New York Stock Exchange (XNYS)