Blocklisting Interim Review

Henderson High Income Trust PLC
05 July 2007


                        BLOCK LISTING SIX MONTHLY RETURN

Information provided on this form must be typed or printed electronically.

To:  The FSA

Date: 5 JULY 2007

Name of applicant:                                         HENDERSON HIGH INCOME TRUST PLC

Name of scheme:                                            Henderson Investment Trust Share Plan and Direct Dealing
                                                           Service

Period of return:                           From:          5 January 2007         To:        4 July 2007

Balance under scheme from previous return:                 1,482,712 ordinary shares of 5p each

The amount by which the block scheme has been increased,   Nil
if the scheme has been increased since the date of the
last return:

Number of securities issued/allotted under scheme during   Nil
period:

Balance under scheme not yet issued/allotted at end of     1,482,712 ordinary shares of 5p each
period

Number and class of securities originally listed and the   400,000 ordinary shares on 16 June 1993
date of admission                                          1,308,971 ordinary shares on 13 November 2001
                                                           1,353,637 ordinary shares on 7 June 2002
                                                           1,365,187 ordinary shares on 11 June 2002
                                                           1,388,888 ordinary shares on 12 June 2002

Total number of securities in issue at the end of the      85,835,744 ordinary shares of 5p each
period

Name of contact:                                           Deborah Trickett

Address of contact:                                        Henderson Global Investors, 4 Broadgate, London EC2M 2DA

Telephone number of contact:                               020 7818 6816



SIGNED BY   ______________________________________________

            Deborah Trickett, for and on behalf of Henderson Secretarial Services Limited,
            Company Secretary to
            Henderson High Income Trust plc


If you knowingly or recklessly give false or misleading information you may be
liable to prosecution.


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