CERTIFICATIONS PURSUANT TO SECTION 906

EX-99.906CERT

CERTIFICATION

R. Jay Gerken, Chief Executive Officer, and Richard F. Sennett, Principal Financial Officer of Master Portfolio Trust– Municipal High Income Portfolio (the “Registrant”), each certify to the best of his knowledge that:

1. The Registrant’s periodic report on Form N-CSR for the period ended January 31, 2013 (the “Form N-CSR”) fully complies with the requirements of section 15(d) of the Securities Exchange Act of 1934, as amended; and

2. The information contained in the Form N-CSR fairly presents, in all material respects, the financial condition and results of operations of the Registrant.

Chief Executive Officer	Principal Financial Officer
Master Portfolio Trust-	Master Portfolio Trust-
Municipal High Income Portfolio	Municipal High Income Portfolio
/s/ R. Jay Gerken	/s/ Richard F. Sennett
R. Jay Gerken	Richard F. Sennett
Date: March 25, 2013	Date: March 25, 2013

This certification is being furnished to the Securities and Exchange Commission solely pursuant to 18 U.S.C. § 1350 and is not being filed as part of the Form N-CSR with the Commission.