The group of monks made £8.8m between 2014 to 2015. Most of the money came from sales of its caffeinated, 15-percent-strength Buckfast tonic.
Virtually all of that money was spent, with the Charity Commission saying nearly two-thirds of it (£5.28m) went to charitable activities.
Expenditures included millions of pounds to restore the abbey and visitor facilities. Buckfast Abbey has also set aside £3 million to improve its 33-bedroom hotel and conference centre.
The monks of the abbey host regular services and confessions for the public alongside their personal and group devotions.
Some have been critical of the money Buckfast Abbey has made, citing a link between its tonic wine and violence - especially in Scotland.
Strathclyde Police told the BBC that between 2010 and 2012, Buckfast tonic was mentioned in almost 6,500 crime reports.
Last week a Scottish sheriff said the drink fuels violence, while Alcohol Focus Scotland said this week that there was increasing evidence that caffeinated alcoholic drinks caused particular damage in society.
Premier has contacted Buckfast Abbey for a response.