REPORT OF INDEPENDENT REGISTERED PUBLIC
ACCOUNTING FIRM

To the Shareholders of BlackRock California Municipal
Opportunities Fund, BlackRock New Jersey Municipal
Bond Fund, BlackRock Pennsylvania Municipal Bond Fund,
and BlackRock Strategic Municipal Opportunities Fund and
the Boards of Trustees of BlackRock California Municipal
Series Trust, BlackRock Multi-State Municipal Series Trust,
and BlackRock Municipal Series Trust:

In planning and performing our audits of the financial
statements of BlackRock California Municipal Opportunities
Fund of BlackRock California Municipal Series Trust,
BlackRock New Jersey Municipal Bond Fund and BlackRock
Pennsylvania Municipal Bond Fund of BlackRock Multi-State
Municipal Series Trust, and BlackRock Strategic Municipal
Opportunities Fund of BlackRock Municipal Series Trust (the
"Funds") as of and for the year ended May 31, 2021, in
accordance with the standards of the Public Company
Accounting Oversight Board (United States) (PCAOB), we
considered the Funds' internal control over financial reporting,
including controls over safeguarding securities, as a basis for
designing our auditing procedures for the purpose of expressing
our opinion on the financial statements and to comply with the
requirements of Form N-CEN, but not for the purpose of
expressing an opinion on the effectiveness of the Funds' internal
control over financial reporting. Accordingly, we express no
such opinion.

The management of the Funds is responsible for establishing
and maintaining effective internal control over financial
reporting. In fulfilling this responsibility, estimates and
judgments by management are required to assess the expected
benefits and related costs of controls. A company's internal
control over financial reporting is a process designed 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. A company's internal control over financial reporting
includes those policies and procedures that (1) pertain to the
maintenance of records that, in reasonable detail, accurately and
fairly reflect the transactions and dispositions of the assets of the
company; (2) provide reasonable assurance that transactions are
recorded as necessary to permit preparation of financial
statements in accordance with generally accepted accounting
principles, and that receipts and expenditures of the company
are being made only in accordance with authorizations of
management and directors of the company; and (3) provide
reasonable assurance regarding prevention or timely detection of
unauthorized acquisition, use, or disposition of a company's
assets that could have a material effect on the financial
statements.

Because of its inherent limitations, internal control over
financial reporting may not prevent or detect misstatements.
Also, projections of any evaluation of effectiveness to future
periods are subject to the risk that controls may become
inadequate because of changes in conditions, or that the degree
of compliance with the policies or procedures may deteriorate.
A deficiency in internal control over financial reporting exists
when the design or operation of a control does not allow
management or employees, in the normal course of performing
their assigned functions, to prevent or detect misstatements on a
timely basis. A material weakness is a deficiency, or a
combination of deficiencies, in internal control over financial
reporting, such that there is a reasonable possibility that a
material misstatement of the company's annual or interim
financial statements will not be prevented or detected on a
timely basis.

Our consideration of the Funds' internal control over financial
reporting was for the limited purpose described in the first
paragraph and would not necessarily disclose all deficiencies in
internal control that might be material weaknesses under
standards established by the PCAOB. However, we noted no
deficiencies in the Funds' internal control over financial
reporting and its operation, including controls for safeguarding
securities, that we consider to be a material weakness, as
defined above, as of May 31, 2021.

This report is intended solely for the information and use of
management and the Board of Trustees of the Funds and the
Securities and Exchange Commission and is not intended to be
and should not be used by anyone other than these specified
parties.

/s/Deloitte & Touche LLP
Boston, Massachusetts
July 21, 2021