| **ORGANIZATION**                                                                             | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
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| **Organization, Consolidation and Presentation Of Financial Statements [Abstract]**          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] | NOTE A - ORGANIZATION
Boston Capital Tax Credit Fund Limited Partnership (the "Partnership") was formed under the laws of the State of Delaware as of September 1, 1988, for the purpose of acquiring, holding, and disposing of limited partnership interests in operating partnerships which have acquired, developed, rehabilitated, operate and own newly constructed, existing or rehabilitated low-income apartment complexes ("Operating Partnerships"). On August 22, 1988, American Affordable Housing VI Limited Partnership changed its name to Boston Capital Tax Credit Fund Limited Partnership. Effective as of June 1, 2001 there was a restructuring, and as a result, the Partnership's general partner was reorganized as follows. The general partner of the Partnership continues to be Boston Capital Associates Limited Partnership, a Massachusetts limited partnership. The general partner of the general partner of the Partnership is BCA Associates Limited Partnership, a Massachusetts limited partnership whose sole general partner is C&M Management, Inc., a Massachusetts corporation whose limited partners are Herbert F. Collins and John P. Manning. Mr. Manning is the principal of Boston Capital Partners, Inc. The limited partner of the general partner is Capital Investment Holdings, a general partnership whose partners are officers and employees of Boston Capital Partners, Inc. and its affiliates. The assignor limited partner is BCTC Assignor Corp., a Delaware corporation which is now wholly-owned by John P. Manning.

Pursuant to the Securities Act of 1933, the Partnership filed a Form S-11 Registration Statement with the Securities and Exchange Commission, effective August 29, 1988, which covered the offering (the "Public Offering") of the Partnership's beneficial assignee certificates ("BACs") representing assignments of units of the beneficial interest of the limited partnership interest of the assignor limited partner. The Partnership registered 10,000,000 BACs at $10 per BAC for sale to the public in six series. Offers and sales of BACs in Series 1 through Series 6 of the Partnership were completed and the last of the BACs in Series 6 were issued by the Partnership on September 29, 1989. The Partnership sold 1,299,900 of Series 1 BACs, 830,300 of Series 2 BACs, 2,882,200 of Series 3 BACs, 2,995,300 of Series 4 BACs, 489,900 of Series 5 BACs and 1,303,000 of Series 6 BACs. As of June 30, 2012 1,296,900 of Series 1 BACs, 829,800 of Series 2 BACs, 2,864,200 of Series 3 BACs, 2,991,300 of Series 4 BACs, 489,900 of Series 5 BACs and 1,303,000 of Series 6 BACs, respectively, are outstanding. The Partnership is no longer offering and does not intend to offer any additional BACs. |

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| - Definition
The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.
+ References
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