N-CSR Item 12(a)(2) - Exhibits: Certifications


I, J. Christopher Donahue, certify that:

1.   I have  reviewed this report on Form N-CSR of Federated  Income  Securities
     Trust  on  behalf  of:  Federated  Intermediate  Corporate  Bond  Fund  and
     Federated Short-Term Income Fund ("registrant");

2.   Based on my knowledge, this report does not contain any untrue statement of
     a material  fact or omit to state a  material  fact  necessary  to make the
     statements made, in light of the circumstances  under which such statements
     were made,  not  misleading  with  respect  to the  period  covered by this
     report;

3.   Based on my  knowledge,  the  financial  statements,  and  other  financial
     information  included  in  this  report,  fairly  present  in all  material
     respects the financial  condition,  results of  operations,  changes in net
     assets, and cash flows (if the financial statements are required to include
     a statement  of cash flows) of the  registrant  as of, and for, the periods
     presented in this report;

4.   The  registrant's  other  certifying  officers  and I are  responsible  for
     establishing and maintaining disclosure controls and procedures (as defined
     in rule  30a-3(c)  under the  Investment  Company Act of 1940) and internal
     control over  financial  reporting (as defined in Rule  30a-3(d)  under the
     Investment Company Act of 1940) for the registrant and have:

a.   designed such disclosure controls and procedures, or caused such disclosure
     controls and  procedures to be designed  under our  supervision,  to ensure
     that  material  information  relating  to  the  registrant,  including  its
     consolidated  subsidiaries,  is made  known to us by  others  within  those
     entities,  particularly  during the  period in which  this  report is being
     prepared;

b.   Designed such internal  control over  financial  reporting,  or caused such
     internal  control  over  financial  reporting  to  be  designed  under  our
     supervision,  to provide reasonable  assurance regarding the reliability of
     financial  reporting  and  the  preparation  of  financial  statements  for
     external  purposes  in  accordance  with  generally   accepted   accounting
     principles;

c.   evaluated the  effectiveness  of the registrant's  disclosure  controls and
     procedures  and  presented  in  this  report  our  conclusions   about  the
     effectiveness  of the  disclosure  controls  and  procedures,  as of a date
     within  90 days  prior  to the  filing  date of this  report  based on such
     evaluation; and

d.   disclosed in this report any change in the  registrant's  internal  control
     over financial  reporting that occurred during the second fiscal quarter of
     the period  covered by this  report  that has  materially  affected,  or is
     reasonably likely to materially affect,  the registrant's  internal control
     over financial reporting; and

5.   The  registrant's  other  certifying  officers and I have  disclosed to the
     registrant's  auditors and the audit committee of the registrant's board of
     directors (or persons performing the equivalent functions):

a.   all  significant  deficiencies  and  material  weaknesses  in the design or
     operation of internal control over financial reporting which are reasonably
     likely to adversely  affect the  registrant's  ability to record,  process,
     summarize, and report financial information; and

b.   any fraud,  whether or not  material,  that  involves  management  or other
     employees who have a significant role in the registrant's  internal control
     over financial reporting.




Date: June 22, 2005
/S/ J. Christopher Donahue
President - Principal Executive Officer






     N-CSR Item 12(a)(2) - Exhibits: Certifications


I, Richard J. Thomas, certify that:

1.   I have  reviewed this report on Form N-CSR of Federated  Income  Securities
     Trust  on  behalf  of:  Federated  Intermediate  Corporate  Bond  Fund  and
     Federated Short-Term Income Fund ("registrant");

2.   Based on my knowledge, this report does not contain any untrue statement of
     a material  fact or omit to state a  material  fact  necessary  to make the
     statements made, in light of the circumstances  under which such statements
     were made,  not  misleading  with  respect  to the  period  covered by this
     report;

3.   Based on my  knowledge,  the  financial  statements,  and  other  financial
     information  included  in  this  report,  fairly  present  in all  material
     respects the financial  condition,  results of  operations,  changes in net
     assets, and cash flows (if the financial statements are required to include
     a statement  of cash flows) of the  registrant  as of, and for, the periods
     presented in this report;

4.   The  registrant's  other  certifying  officers  and I are  responsible  for
     establishing and maintaining disclosure controls and procedures (as defined
     in rule  30a-3(c)  under the  Investment  Company Act of 1940) and internal
     control over  financial  reporting (as defined in Rule  30a-3(d)  under the
     Investment Company Act of 1940) for the registrant and have:

a.   designed such disclosure controls and procedures, or caused such disclosure
     controls and  procedures to be designed  under our  supervision,  to ensure
     that  material  information  relating  to  the  registrant,  including  its
     consolidated  subsidiaries,  is made  known to us by  others  within  those
     entities,  particularly  during the  period in which  this  report is being
     prepared;

b.   Designed such internal  control over  financial  reporting,  or caused such
     internal  control  over  financial  reporting  to  be  designed  under  our
     supervision,  to provide reasonable  assurance regarding the reliability of
     financial  reporting  and  the  preparation  of  financial  statements  for
     external  purposes  in  accordance  with  generally   accepted   accounting
     principles;

c.   evaluated the  effectiveness  of the registrant's  disclosure  controls and
     procedures  and  presented  in  this  report  our  conclusions   about  the
     effectiveness  of the  disclosure  controls  and  procedures,  as of a date
     within  90 days  prior  to the  filing  date of this  report  based on such
     evaluation; and

d.   disclosed in this report any change in the  registrant's  internal  control
     over financial  reporting that occurred during the second fiscal quarter of
     the period  covered by this  report  that has  materially  affected,  or is
     reasonably likely to materially affect,  the registrant's  internal control
     over financial reporting; and

5.   The  registrant's  other  certifying  officers and I have  disclosed to the
     registrant's  auditors and the audit committee of the registrant's board of
     directors (or persons performing the equivalent functions):

a.   all  significant  deficiencies  and  material  weaknesses  in the design or
     operation of internal control over financial reporting which are reasonably
     likely to adversely  affect the  registrant's  ability to record,  process,
     summarize, and report financial information; and

b.   any fraud,  whether or not  material,  that  involves  management  or other
     employees who have a significant role in the registrant's  internal control
     over financial reporting.




Date: June 22, 2005
/S/ Richard J. Thomas
Treasurer - Principal Financial Officer