v3.3.0.814

Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2015	Nov. 12, 2015
Entity Registrant Name	Reef Oil & Gas Income & Development Fund III LP
Entity Central Index Key	0001411643
Document Type	10-Q
Document Period End Date	Sep. 30, 2015
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Smaller Reporting Company
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q3
General Partner
Entity Common Stock, Shares Outstanding		490.7327
General Partner Interest Held by Managing General Partner
Entity Common Stock, Shares Outstanding		9.2197
Limited Partner Interest Held by Managing General Partner
Entity Common Stock, Shares Outstanding		1.0500
Limited Partner
Entity Common Stock, Shares Outstanding		395.9672

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Reef Oil & Gas Income & Development Fund III LP 10-Q