    <SEC-DOCUMENT>0001193125-25-159952-index.html : 20250716
    <SEC-HEADER>0001193125-25-159952.hdr.sgml : 20250716
    <ACCEPTANCE-DATETIME>20250716171422
    ACCESSION NUMBER:		0001193125-25-159952
    CONFORMED SUBMISSION TYPE:	N-14 8C
    PUBLIC DOCUMENT COUNT:		11
    FILED AS OF DATE:		20250716
    DATE AS OF CHANGE:		20250716

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			BLACKROCK MUNIASSETS FUND, INC.
    		CENTRAL INDEX KEY:			0000901243
    		ORGANIZATION NAME:
    		EIN:				223239638
    		STATE OF INCORPORATION:			MD
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		N-14 8C
    		SEC ACT:		1933 Act
    		SEC FILE NUMBER:	333-288712
    		FILM NUMBER:		251128077

    	BUSINESS ADDRESS:
    		STREET 1:		100 BELLEVUE PARKWAY
    		CITY:			WILMINGTON
    		STATE:			DE
    		ZIP:			19809
    		BUSINESS PHONE:		800-441-7762

    	MAIL ADDRESS:
    		STREET 1:		100 BELLEVUE PARKWAY
    		CITY:			WILMINGTON
    		STATE:			DE
    		ZIP:			19809

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	MUNIASSETS FUND INC
    		DATE OF NAME CHANGE:	19930714

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	MUNIINCOME FUND INC
    		DATE OF NAME CHANGE:	19930517
    <IS-FUND-24F2-ELIGIBLE>N
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>N-14 8C
    <SEQUENCE>1
    <FILENAME>d80760dn148c.htm
    <DESCRIPTION>BLACKROCK MUNIASSETS FUND, INC.
    <TEXT>
    Document 1 - file: d80760dn148c.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.(12)
    <SEQUENCE>2
    <FILENAME>d80760dex9912.htm
    <DESCRIPTION>FORM OF TAX OPINION OF WILLKIE FARR & GALLAGHER LLP
    <TEXT>
    Document 2 - file: d80760dex9912.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.(16)
    <SEQUENCE>3
    <FILENAME>d80760dex9916.htm
    <DESCRIPTION>POWER OF ATTORNEY OF THE BOARD OF DIRECTORS
    <TEXT>
    Document 3 - file: d80760dex9916.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.(17)
    <SEQUENCE>4
    <FILENAME>d80760dex9917.htm
    <DESCRIPTION>FORM OF PROXY CARD
    <TEXT>
    Document 4 - file: d80760dex9917.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-FILING FEES
    <SEQUENCE>5
    <FILENAME>d80760dexfilingfees.htm
    <DESCRIPTION>CALCULATION OF FILING FEE TABLES
    <TEXT>
    Document 5 - file: d80760dexfilingfees.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>7
    <FILENAME>g80760dsp265.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 7 - file: g80760dsp265.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>8
    <FILENAME>g80760dsp266.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 8 - file: g80760dsp266.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>9
    <FILENAME>g80760dsp271.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 9 - file: g80760dsp271.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>10
    <FILENAME>g80760dsp272.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 10 - file: g80760dsp272.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>11
    <FILENAME>g80760g0711175414398.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 11 - file: g80760g0711175414398.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>12
    <FILENAME>g80760g95a95.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 12 - file: g80760g95a95.jpg

    </DOCUMENT>
    </SEC-DOCUMENT>