The two-day gathering in August for 17 movers and shakers, hosted by the finance minister, was held at a country inn this year in nearby Wakefield, Que.
Hospitality cost more than $6,800, including meals and wine, while facilities and rentals were almost $8,000.
Travel and accommodation for some participants was another $1,500.
Flaherty had to personally approve the hospitality expenses because they exceeded the $5,000 threshold set by government policy — and because alcohol was served.
Participants were treated to breakfast, two lunches, dinner and a reception, the costs of which were higher than the standard per-person guideline set by Treasury Board.
Details of the expenses were obtained by The Canadian Press under the Access to Information Act, with further details from the federal Finance Department.
Guests mostly comprised CEOs from key Canadian industries, but also included an academic, a think-tank executive, a First Nation chief and even a business journalist, the CBC's Amanda Lang.
The retreat offers the group privileged access to the economy's most important decision-maker.
The meeting expense comes at a time of government belt-tightening and thousands of layoffs in the public service, but a spokesman for Flaherty said there was good value for the money.
"These gatherings provide an opportunity for the minister to get advice outside of government," Chisholm Pothier said in an email.
"These Canadians deal with real problems every day and we want to hear from them."
"Our attendees, except for those from the charitable and academic sectors, pay their own air fare, transportation and accommodation costs, but most importantly they give their valuable time.
"Having a glass or two of wine over dinner at the end of the night is normal for such gatherings."
The cost of last year's annual retreat, with 22 guests, was also slightly more than $16,000, with the hospitality tab at almost $8,000.
Flaherty's responsibility for the $6,800 Wakefield hospitality bill is not included in his ministerial travel-and-hospitality expense claims posted on the web because the cost is classed as departmental rather than attributed to the minister.
The Wakefield bill is also separate from the hospitality expenses Flaherty runs up as a member of Parliament, which were $9,323.57 in the fiscal year ending March 31, 2013.
Prime Minister Stephen Harper has himself been required to sign large hospitality expense claims, including a 2011 event for visiting European bureaucrats that cost $16,000, and another for his own staff for $7,400.
However, Harper quietly delegated signing responsibility last year to his senior public servant, the clerk of the Privy Council. Wayne Wouters approved $43,550 in hospitality costs at three events in the first six months after receiving signing authority.
The Conservative government has at least three times tightened its policies on hospitality spending, including last October when it restricted the scope of what constitutes hospitality.
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