Business travel forecast slightly less upbeat

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U.S. business travel spending is on the rise this year, it's just not quite as exuberant as earlier forecasts predicted, according to the quarterly report issued Tuesday by the Global Business Travel Association.

The scaled-back forecast is due to a decline in average spending per trip, mainly due to business travelers visiting fewer cities per trip, said Michael McCormick, executive director and chief operating officer of the Global Business Travel Association.

"We're not sure if it's a trend," McCormick said of the per-trip spending decline, which only started this past quarter. "We don't know if it will continue."

It's not limited to any specific sectors or regions. "So far it's across the board," McCormick said.

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U.S. business travel spending is expected to rise 6.8 percent, to $292.3 billion, in 2014, according to the second-quarter edition of the GBTA Business Travel Index Outlook for the United States, which is sponsored by Visa. In April, the GBTA's quarterly forecast was a more optimistic 7.1 percent, up from January's forecast of 6.6 percent for 2014.

Despite the slight reduction in the forecast, the numbers remain on a slow and steady course upward, McCormick said. He also emphasized the spending appears to be shrugging off any stock market drama, Russian embargo news or even World Cup matches.

"They don't have any impact on these numbers overall. In a global economy we're becoming more resilient," McCormick said.

Consumers may want to take note of one portion of the forecast: pricing. "We still expect travel price growth to remain relatively low through 2014 (1.9 percent) before picking up pace in 2015 (3.2 percent)," the GBTA report states. The 2015 price rise will come mainly in increased prices at hotels, restaurants and for rental cars.

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Indeed, U.S. hotel rates have been slowly rising all year. The average daily rate for a U.S. hotel for the week ended June 28 was $116.90, up 4.9 percent from a year ago, according to STR hotel research firm. In the top 25 markets, the steepest increases were in Seattle (at $156.65) and New Orleans ($131.56,) each with a 16.8 percent increase over the same period last year.

By the end of 2015, U.S. hotels rates are expected to increase 4.2 percent on average, with the steepest increase on the luxury level, where rates will likely rise 5.4 percent over 2014, said Jan Freitag, a senior vice president at Tennessee-based STR travel research.

In addition, some of those business travel expenses are getting harder to track, according to an IDC report based on the findings from users of Concur business travel and expense management software.

The report found more travelers are skipping the preferred travel management company (TMC) and booking directly through the airline or hotel, creating an "invisible spend." According to a spokeswoman for Concur, 40 to 50 percent of hotel bookings and 28 percent of air bookings are considered invisible spend.

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—By CNBC's Amy Langfield. Follow Road Warrior on Twitter at @CNBCtravel.