Road Warrior

Super Bowl bound? You might want to book now

Harriet Baskas, Special to CNBC

The jury's still out on which teams will be heading to Glendale, Arizona, to compete in Super Bowl XLIX on Feb. 1.

Yet an estimated 100,000 out-of-state fans will be heading that way soon and are searching for deals on airfare and hotels now. Depending on when you travel and where you stay, the price of the trip can be surprisingly affordable.

"We're at that 21-day advance purchase window where things definitely start to get interesting in terms of air ticket prices," said Jeremy Boore, analytics manager for Expedia.

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For flights from cities with teams still in the running, Boore looked at Phoenix-bound flights departing between Jan. 26 and Feb. 1, and returning between Feb. 2 and Feb. 5. He found fares from Boston ($280-$700) and Denver ($100-$600) were unchanged since last week, while those from North Carolina ($375-$765), Baltimore-Washington International ($260-$725) and Seattle ($270-$500) had decreased slightly.

Flights from Green Bay, Wisconsin ($300-$575) and Dallas-Fort Worth ($80-$250) rose modestly, while the range of prices for flights from Indianapolis ($275-$625) jumped sharply.

For ardent fans willing to spend the cash on a trip, Boore suggests the time to act is now.

"At this three-week window, fares start to shoot up about at an average of 2 percent a day," he said, noting that bigger bumps arrive at seven and 14 days out. "So 21 days out is the best bet to find a deal."