Web-surfing consumers prefer to book their lodging with third-party online distributors over hotel Web sites for their mid-year travel, crimping hotel profits during a season that should otherwise be highly lucrative, a new study shows.

The report was issued as a stern pre-season warning to hotel companies. The big hotel brands stand to lose a total $250 million in reservations this year, says Compete Inc., a Boston market research firm and author of the study.

“Without a change in their marketing, hotels will experience another seasonal slip in share as consumers return to aggregators to book their mid–year travel,” said Gregory Saks, a Compete senior associate and analyst.

Between April and July, the Compete study said, consumers tend to shop aggregators like Priceline, Expedia and Travelocity rather than hotel sites. That translates into a market share loss of 5 to 10 percentage points, or more than 500,000 reservations among the hotel brands the firm studied.

In large measure, hotels are more effective marketing to frequent travelers than to summer travelers, who are less familiar with booking options and more likely to make just that one summer trip, Saks said.

“Orbits, Expedia and Travelocity have built strong brands among those infrequent travelers,” Saks said. “That’s top of mind for them, so they go directly to them without considering a brand site.”

The report wasn’t entirely bleak. Hotels are making “steady inroads” on aggregators, with consumer bookings through hotel brand sites rising more than 60 percent over the past year, Compete said. In contrast, online reservations at Priceline, Expedia and Travelocity have grown 31 percent, 16 percent and 8 percent respectively.

Hotel companies that have gained market share have tapped a consumer penchant for convenience and cost savings. To sell to more summer travelers, however, Compete says lodging companies must beef up their marketing when it comes to pitching best rate guarantees.

“The repercussions of a renewed seasonal slip can be quite damaging in the future,” the report said. Hotel referral fees to aggregators, sometimes amounting to as much as 30 percent of a reservation, can measure in the hundreds of millions of dollars.

Further, the report said, “increased consumer use of aggregators makes it more difficult for hotels to build a base of profitable and loyal customers, pitting hotels against each other in an effort to win reservations.”

Specific findings for hotel brand sites on how to combat the seasonal slide:

- Consumers feel aggregators provide better options, advocacy and price. Consumers who made reservations at aggregator sites feel they receive a better nightly price than they would through a hotel brand site. They prize aggregators’ breadth and neutrality, but do not value the opportunity to bundle travel plans or earn extra rewards.

- Consumers feel hotel brand sites provide a better “total travel experience.” Consumers choose to book reservations directly through hotel brand sites when they have a positive prior stay within the location and/or chain. They also place a premium on factors beyond online booking, specifically flexible cancellation policies and rewards programs.

- Consumers will book with brand sites if provided the best price and other perks. Three in four consumers said a best rate guarantee would have a significant impact on their decision to book through a hotel brand site versus an aggregator. In addition, half the consumers identified complimentary room service and breakfast as a significant factor, and one-third said online check-in was significant.

- Frequent aggregator customers are willing to switch to book directly with hotels. 75% of consumers who made an online reservation through an aggregator said they would purchase directly from a hotel brand site if they could receive the exact same price.

- Awareness of hotel best rate programs is extremely low, but demand is high. Fewer than 5 percent of consumers who visit a hotel brand site interact with content regarding their best rate guarantee, and 28 percent of consumers who made a reservation at a hotel brand site recalled seeing any best rate guarantee messaging. However, among consumers who made reservations and recalled best rate guarantee messaging, more than 70 percent said it influenced their purchase decision.

Compete analyzed consumer online travel research and buying behavior across brands including Intercontinental Hotels Group, the Hilton Hotels, the Marriot family of hotels, Starwood hotels, Carlson Hotels Worldwide, Expedia, Hotels.com, Hotwire, Orbitz, Priceline and Travelocity.