DOCUMENT AND ENTITY INFORMATION	6 Months Ended
Sep. 30, 2011
Entity Registrant Name	BOSTON FINANCIAL TAX CREDIT FUND VIII LP
Entity Central Index Key	0000911568
Current Fiscal Year End Date	--03-31
Entity Filer Category	Smaller Reporting Company
Trading Symbol	bftcviii
Entity Common Stock, Shares Outstanding	0
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2011
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2012

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