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v3.25.2

N-2 | Aug. 22, 2025
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Cover [Abstract] |
Entity Central Index Key | 0001562818
Amendment Flag | false
Entity Inv Company Type | N-2
Securities Act File Number | 333-285442
Investment Company Act File Number | 811-22774
Document Type | POS EX
Document Registration Statement | true
Pre-Effective Amendment | false
Post-Effective Amendment | true
Post-Effective Amendment Number | 2
Investment Company Act Registration | true
Investment Company Registration Amendment | true
Investment Company Registration Amendment Number | 13
Entity Registrant Name | BlackRock Multi-Sector Income Trust
Entity Address, Address Line One | 100 Bellevue Parkway
Entity Address, City or Town | Wilmington
Entity Address, State or Province | DE
Entity Address, Postal Zip Code | 19809
City Area Code | 800
Local Phone Number | 882‑0052
Approximate Date of Commencement of Proposed Sale to Public | From time to time after the effective date of this Registration Statement.
Dividend or Interest Reinvestment Plan Only | false
Delayed or Continuous Offering | true
Primary Shelf [Flag] | true
Effective Upon Filing, 462(e) | true
Additional Securities Effective, 413(b) | false
Effective when Declared, Section 8(c) | false
New Effective Date for Previous Filing | false
Additional Securities. 462(b) | false
No Substantive Changes, 462(c) | false
Exhibits Only, 462(d) | true
Registered Closed-End Fund [Flag] | true
Business Development Company [Flag] | false
Interval Fund [Flag] | false
Primary Shelf Qualified [Flag] | true
Entity Well-known Seasoned Issuer | No
Entity Emerging Growth Company | false
New CEF or BDC Registrant [Flag] | false
Business Contact [Member] |
Cover [Abstract] |
Entity Address, Address Line One | 50 Hudson Yards
Entity Address, City or Town | New York
Entity Address, State or Province | NY
Entity Address, Postal Zip Code | 10001
Contact Personnel Name | John M. Perlowski, President

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